Proceedings of the World Congress on Engineering and Computer Science 2010 Vol I WCECS 2010, October 20-22, 2010, San Francisco, USA How to Prove the Riemann Hypothesis Fayez Fok Al Adeh. Abstract- To prove the Riemann Hypothesis is to show that the nontrivial zeros of the Riemann zeta function, which are complex, have real part equal to 0.5 . The proof given herein is divided into two parts. Integral calculus is used in the first part, while variational calculus is employed in the second part. Given that (a) is the real part of any nontrivial zero of the Riemann zeta function, it is assumed that (a) is a fixed exponent in the equations 50-59 and hence it is verified that a=0.5. In the remaining equations beginning in equation (60) (a) is treated as a parameter (a<0.5) and a contradiction is obtained. At the end of the proof (from equation (73) onward), it is verified again that a = 0.5 Index Terms-Functional Equation, L'Hospital's Rule, Variational Caculus. Subj-class: Functional analysis, complex variables, general mathematics. I. INTRODUCTION The Riemann zeta function is the function of the complex variable s = a + bi (i = − 1 ), defined in the half plane a >1 by the absolute convergent series ∞ 1 ζ (s) = ∑ (1) s 1 n and in the whole complex plane by analytic continuation. The function ζ (s ) has zeros at the negative even integers -2, 4, … and one refers to them as the trivial zeros. The Riemann Hypothesis states that the nontrivial zeros of ζ (s ) have real part equal to 0.5. II, PROOF OF THE RIEMANN HYPOTHESIS We begin with the equation ζ (s) =0 (2) where s= a+bi (3) i.e. ζ ( a + bi ) = 0 (4) It is known that the nontrivial zeros of ζ (s ) are all complex. Their real parts lie between zero and one. If 0 < a < 1 then ζ (s) ∞ =s [ x] − x ∫0 x s + 1 dx (0 < a < 1) (5) [x] is the integer function ∞ ∫x Separating the real and imaginary parts we get ∞ ∫x − 1 − a ([ x] − x) cos(b log x)dx = 0 (10) − 1 − a ([ x] − x) sin(b log x)dx = 0 (11) 0 ∞ ∫x 0 According to the functional equation, if Hence we get besides (11) ∞ − 1 − a − bi dx = 0 0 ∞ ∫y − 1 − a ([ y ] − y ) sin(b log y )dy = 0 ∫ ([ x] − x) x − 1 − a x − bi dx = 0 (13) 0 We form the product of the integrals (12)and (13).This is justified by the fact that both integrals (12) and (13) are absolutely convergent .As to integral (12) we notice that ∞ ∫ x − 2 + a ([ x] − x) sin(b log x)dx ≤ ∞ x− 2 + a ∫ 0 0 ([x]-x) sin (blog x) ∞ ∫x ≤ dx − 2 + a (( x))dx 0 ( where ((z)) is the fractional part of z , 0 ≤ ((z))<1) 1− t = lim(t → 0) ∫ x −1 + a dx + lim (t → 0 ) 0 ∞ x − 2 + a ((x))dx ∫ 1+t (t is avery small positive number) (since ((x)) =x whenever 0 ≤ x<1) ∞ = 1 − 2 + a ((x))dx + lim (t → 0 ) ∫ x a 1+t < 1 − 2 + a dx = 1 + 1 + lim (t → 0 ) ∫ x a a a −1 1+t ∞ (6) ∞ As to integral (13) (7) ≤ (8) 0 Manuscript received May 8, 2010. Fayez Fok Al Adeh is the President of the Syrian Cosmological Society ∫y − 1 − a ([ y ] − y ) sin(b log y )dy 0 ∞ 0 ∞ (12) In (11) replace the dummy variable x by the dummy variable y Therefore ∫ ([ x] − x) x ζ (s) =0 then ζ (1 − s) =0. − 2 + a ([ x] − x) sin(b log x)dx = 0 ∫x ∞ ∞ (9) 0 Hence [ x] − x ∫0 x s + 1 dx = 0 − 1 − a ([ x ] − x )(cos( b log x ) − i sin( b log x )) dx = 0 y − 1 − a ([ y ] − y ) sin(b log y ) ∫ dy 0 ∞ ≤ ∫y − 1 − a (( y ))dy 0 (Phone 00963 – 11 – 2713005; email: [email protected]; airmail address: P.O.Box 13187 Damascus Syria). ISBN: 978-988-17012-0-6 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) WCECS 2010 Proceedings of the World Congress on Engineering and Computer Science 2010 Vol I WCECS 2010, October 20-22, 2010, San Francisco, USA 1−t = lim (t → 0) ∫ Rewrite this integral in the equivalent form y − a dy + lim(t → 0 ) ∞∞ ∫∫x 0 ∞ 0 0 ∞∞ 0 0 (t is avery small positive number) (since ((y)) =y whenever 0 ≤ y<1) 1 − 1 − a (( y ))dy + lim(t → 0 ) ∫ y 1− a 1+t ∞∞ ∫∫x ∞ 1 − 1 − a dy = 1 + 1 + ∫ y 1 − a 1+t 1− a a ∫∫x 1 {( x 2 − 2a [ ] − x − 2 + a y − 1 − a ([ x] − x)([ y ] − y ) (14) 0 0 sin(b log y ) sin(b log x)dxdy = 0 Thus ∞ ∞ ∫∫x − 2 + a y − 1 − a ([ x ] − x )([ y ] − y ) (15) 0 0 (cos( b log y + b log x ) − cos( b log y − b log x )) dxdy = 0 ∞ ∞ ∫∫x − 2 + a y − 1 − a ([ x ] − x )([ y ] − y ) 0 0 (cos( b log xy ) − cos( b log (16) y )) dxdy = 0 x limit is given by 1 x − a y − 1 − a [ - (( y)) ] cos (blog xy ) [ - (( )) + x 2a − 2 ] ((x)) x (32) Lim 0 0 The above limit vanishes ,since all the functions [ - ((y)) ] , ∞∞ − 2 + a y − 1 − a ([ x] − x)([ y ] − y ) cos(b log y )dxdy (17) ∫0 ∫0 x x cos (blog xy ), - (( ∞∞ (18) 1 − dz z dx = z 2 ∫∫ F(x,y) dx dy is bounded as follows ∫∫ F(x,y) dx dy = I1 The integral becomes ∞ 0 (19) I1 1 x ∞ 0 (20) I1 This is equivalent to If we replace the dummy variable z by the dummy variable x, the integral takes the form ∞∞ ∫∫x 0 0 − a y − 1 − a ([ 1 ] − 1 )([ y ] − y ) cos(b log xy )dxdy x x ISBN: 978-988-17012-0-6 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) )) + ((x)) (21) (22) ∞ = x − a y − 1 − a [ - (( y)) ] cos (blog x 2a − 2 ∞ ∫ (∫ p )) + ((x)) x 2a − 2 ] dx dy (34) 1 x − a y − 1 − a [ - (( y)) ] cos (blog xy ) [ - (( x ∫∫ ≤ ∞∞ ∫∫ (33) I1 xy ) [ - (( That is − a − 1 − a ([ 1 ] − 1 )([ y ] − y ) cos(b log zy )dzdy ∫0 ∫0 z y z z 1 )), and ((x)) remain bounded as x → ∞ x and y → ∞ Note that the function F (x,y) is defined and bounded in the region I 1. We can prove that the integral Consider the integral on the right-hand side of (17) 1 1 − ∫ ∫ z − a y − 1 − a ([ ] − )([ y ] − y ) cos(b log zy )dzdy z z 0 ∞ )-([x]-x)}dx dy=0 x − 2 + a y − 1 − a ([ y ] − y ) cos( b log xy ) 1 x 2 − 2a 2 2 a − {( x [ ]− )-([x]-x)} (31) x x Let us find the limit of F (x,y) as x → ∞ and y → ∞ . This − 2 + a y − 1 − a ([ x] − x)([ y ] − y ) cos(b log xy )dxdy = ∫∫x 2 − a − 1 − a ([ 1 ] − 1 )([ y ] − y ) cos(b log zy ) − dz dy ∫0 ∞∫ z y z z z2 x (25) Denote the integrand in the left hand side of (25) by F (x,y) = ∞∞ In this integral make the substitution x = x 2 − 2a Let p >0 be an arbitrary small positive number.we consider the following regions in the x –y plane. (26) The region of integration I = [0, ∞ ) ×[0, ∞ ) The large region I1 =[ p, ∞ ) × [ p, ∞ ) (27) The narrow strip I 2 =[ p, ∞ ) × [0,p ] (28) The narrow strip I 3 = [0,p]× [ 0, ∞ ) (29) Note that (30) I = I1 U I 2 U I 3 That is − 2 + a y − 1 − a ([ x] − x)([ y ] − y ) cos(b log y )dxdy ∫0 ∫0 x x − 2 + a y − 1 − a ([ y ] − y ) cos(b log xy) 0 0 Since the limits of integration do not involve x or y , the product can be expressed as the double integral ∞∞ (24) 2 − 2a − 2 + a y − 1 − a ( x 2 − 2a [ 1 ] − x )([ y ] − y ) cos(b log xy )dxdy ∫0 ∫0 x x x Write (24) in the form ∞∞ ∞ < − 2 + a y − 1 − a ([ x] − x)([ y ] − y ) cos(b log xy )dxdy = ∫∫x 1+t = (23) Thus (17) becomes y − 1 − a (( y ))dy ∫ 2 − 2a − 2 + a y − 1 − a ( x 2 − 2a [ 1 ] − x )([ y ] − y ) cos(b log xy )dxdy x x x− a ] dx dy cos (blog xy ) [ - (( p x 2a − 2 ] dx) 1 x )) + ((x)) y − 1 − a [ - (( y)) ]dy WCECS 2010 Proceedings of the World Congress on Engineering and Computer Science 2010 Vol I WCECS 2010, October 20-22, 2010, San Francisco, USA ∞ ≤ ∞ ∫ ( p x− a ∫ p x 2a − 2 ∞ ∞ x− a ( p [ - (( x 2a − 2 ∞ ∫ x− a ] dx) [ (( 1 x Ρ ∞ 1 x x 2a − 2 = ∞ [ (( Ρ 1 x ∫∫ F(x,y) dx dy is bounded ∫∫ F(x,y) dx dy = ∫∫ F(x,y) dx dy ∫ x− a [ (( 1+ t 1 x lim(t → 0) ∫ )) + ((x)) x− a [ (( Ρ ∫ x− a [ (( 1+ t 1 x Since x >1 ,then (( ∞ lim(t → 0) 1 x )) + ((x)) = lim(t → 0) ∫ 1 x )) = 1 x [ (( x− a 1+ t ∞ = lim(t → 0) ∫ x 2a − 2 ≤ ] dx } ] dx ∫ [ )) + ((x)) + ((x)) ≤ x 2a − 2 x 2a − 2 ] dx ∞ ] dx 0 x − a { (( ∫ 1 ya ))- ((x)) − a { (( 1 x 1 ya p (40) dx) 1 x x 2a − 2 } ))- ((x)) x 2a − 2 } dy 1 x ))- ((x)) 1 ya x 2a − 2 } dy ))- ((x)) x 2a − 2 } dx × dy (This is because in this region ((y)) = y). It is evident that the ∞ integral ] dx (39) dy x − a { (( ∫ ∫ ( Ρ Ρ ∫ x − a { (( ∫ Ρ 1 x ))- ((x)) x 2a − 2 } dx is bounded,this was proved in the course of proving that the [x − a −1+ xa − 2 integral ] dx Ρ 1 = a(1 − a) Hence the boundedness of the integral ∫ 0 ∫∫ F(x,y) dx dy is F(x,y) dx dy is bounded .Also it is evident that 1 ya dy is bounded. Thus we deduce that the integral (40) dx dy is bounded I1 ISBN: 978-988-17012-0-6 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) ∫∫ the integral I1 1+ t proved. Consider the region I4=I2 U I3 We know that p ∞ and we have 1 x (x cos(b log xy ) ] dx is bounded. − a − 1 + ((x)) x a − 2 [x ∞ 0) ∫ ∫ p ≤ F(x,y) dx dy F(x,y) dx dy 1 x 1 ya cos(b log xy ) dx) x 2a − 2 1 x ∫∫ x − a { (( ∞ 0 x 2a − 2 ∫∫ I3 ≤ cos(b log xy ) dx) 1+ t < lim(t → F(x,y) dx dy + p p )) + ((x)) )) + ((x)) 1+ t ∞ ∫ (∫ 0 x− a ∫ (38) I2 ∞ p ] dx is bounded, it remains to show that lim(t → 0 ) ∞ ∫∫ I2 where t is a very small arbitrary positive. number.Since the integral 1− t (37) I4 Remember that 0 1 x [ (( F(x,y) dx dy (36) I4 dy = 1− t ∫∫ I1 From which we deduce that the integral ] dx x 2a − 2 )) + ((x)) 1 −a { lim(t → 0 ) ∫ x = ap a Ρ x 2a − 2 ] dx + lim(t → 0 ) ∞ I1 I4 I2 Consider the integral x− a ∫ F(x,y) dx dy + )) + Ρ 1 ap a ∫∫ F(x,y) dx dy is bounded y−1− a ∫ F(x,y) dx dy = ∫∫ y − 1 − a [ - (( y)) ] )) + ((x)) ∫∫ I and that dy p ((x)) < cos (blog xy ) 0= )) + ((x)) y − 1 − a [ - (( y)) ] ] dx) ∫ ∫ ≤ 1 x cos (blog xy ) [ - (( Hence ,according to (39),the integral (35) bounded. ∫∫ F(x,y) I2 ∫∫ F(x,y) dx dy is I3 WCECS 2010 Proceedings of the World Congress on Engineering and Computer Science 2010 Vol I WCECS 2010, October 20-22, 2010, San Francisco, USA Now we consider the integral ∫∫ ∞ F(x,y) dx dy (41) ∫∫ p ∞ ∫ (∫ y −1− a ∞ 0 0 y ∞ ∫ ( 0 p ∞ ∞ y −1− a ∫ −1− a ((y)) cos (b logxy) dy ) dx 1 {(( )) − x 2 a −1 } x xa ((y)) dy ) ((y)) dy dx (43) 1− t = (lim t → 0) ∫ y −1− a × y dy+ (lim t → 0) 0 y −1− a ≤K (44) y −1− a ((y)) cos (b logxy)dy ≤ K (45) p ∞ F(x,y) dx dy = 0 Since 0 ∫ p ∫∫ ( where t is a very small arbitrary positive number) .( Note that ((y))=y whenever 0 ≤ y<1). ∞ Thus we have (lim t → 0) ∫ y −1− a ((y)) dy < y −1− a dy= 1+ t 1− t and (lim t → 0) ∫ y −1− a 1 a ((y)) cos (b logxy) dy) 0 (46) F(x,y) dx dy is bounded, then 1 {(( )) − x 2 a −1 } x dx is bounded xa Hence the integral (43) ∫ y −1− a 1 1− a ∫ 0 1 xa δ { (( 1 x ))- G [F] = (48) G [F] be the variation of the integral G due to the ∫ δ F. F dx (the integral (49) is indefinite ) (49) ( here we do not consider a as a parameter, rather we treat it as a given exponent) We deduce that δG[ F ] =1 δF ( x) that is δ G [F] = δ F (x) But we have ISBN: 978-988-17012-0-6 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) x 2a − 1 } variation of the integrand Since ((y)) dy is bounded. 0 (47) We denote the integrand of (47) by Let × y dy= 0 ∞ G= F= 1+ t ∫ −1− a 1 {(( )) − x 2 a −1 } x dx is also bounded. Therefore xa p 0) y the integral ((y)) dy ∞ ∫ (∫ 1 {(( )) − x 2 a −1 } x dx xa 1 {(( )) − x 2 a −1 } p x ≥ ∫ (− K ) dx xa 0 1 {(( )) − x 2 a −1 } 0 x =K ∫ dx xa p 1+ t (lim t → = H (x) I3 −1− a y 0 ∫ ∫ ≤ ∫∫ Now we consider the integral with respect to y ∞ ((y)) cos (b logxy)dy According to (42) we have 0 y −1− a y 0 –K ((y)) cos (b logxy) dy) 1 {(( )) − x 2 a −1 } x xa ∫ is a bounded function of x ( K is a positive number ) Now (44) gives us 0 ∞ ((y)) cos (b logxy)dy 0 p 0 ∫ (42) 0 ≤ ∫ (∫ −1− a 0 −1− a y ∞ 1 {(( )) − x 2 a −1 } x dx xa ≤ y . Let this function be H(x) . Thus we have ( This is because in this region ((x)) = x ) ∫ (∫ ∫ 0 1 {(( )) − x 2 a −1 } x dx xa ≤ ∫ ((y)) cos (b logxy) dy) I3 −1− a ≤ ((y)) cos (b logxy)dy ((y)) dy , we conclude that the integral 0 p ∞ y ∞ 0 I3 and write it in the form F(x,y) dx dy = ∫ Since −1− a (50) WCECS 2010 Proceedings of the World Congress on Engineering and Computer Science 2010 Vol I WCECS 2010, October 20-22, 2010, San Francisco, USA δ G[F] = ∫ dx δG[ F ] δF (x) δF ( x) (51) p ( the integral (51) is indefinite) Using (50) we deduce that δ G[F] = ∫ dx G = lim (t δF (x) (52) δG = ∫ Ρ dF δx dx dx δF (x) = ∫ dx 0 0 = [ Fδ x ] (at x = p)- [ F δ x ] (at x = 0) (54) Since the value of [ F δ x ] (at x = p)is bounded, we deduce from (54) that lim (x → 0 ) F δ x must remain bounded. (55) Thus we must have that (lim x 1 xa → 0) [ δ x 1 x { (( x 2a − 1 }] ))- (56) x a × δx 0) d (δx) =0 dx x a = (lim x → 1 0 ) × x1− a a 1 x ))- 1 x ) { (( ))- x 2a − 1 } will remain bounded in the limit as (x dx δG a[x] δx = δG a[ x] ∫ dx Thus (64) reduces to p ∫ → 0) G – Fx (at p ) = - lim (t x dF (66) t Note that the left – hand side of (66) is bounded. Equation (63) gives us δ p G a =lim (t → 0) ∫ F δx x dx (67) We can easily prove that the two integrals dx F δx x ∫ x dF and are absolutely convergent .Since the limits of integration do not involve any variable , we form the product of (66) and (67) → 0) (59) p ∫ ∫ t = lim(t → 0)∫ xdF× dx t → 0 ) .Therefore , in F ( x, a ) x x (60) δG a [ x ] δx δx F ( x, a ) ∫ dx x δ x ISBN: 978-988-17012-0-6 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) p FdF × t ∫ F δx x δ xdx (68) t ( K is a bounded quantity ) That is K = lim(t → 0) [ F2 2 ( at p ) - F2 2 (at t) ] × [ (at t) ] We conclude from (69) that {[ F2 2 ( at p) - lim(t is bounded . ( since lim(x → 0) → 0 )δ δ x (at p) - δ x (69) F2 2 (at t) ] ×[ δ x (at p) ] }(70) x = 0 , which is the same thing as (61) → 0 ) δ x = 0) F2 F2 ( at p) is bounded , we deduce at once that must Since 2 2 remain bounded in the limit as (t → 0 ), which is the same thing as saying that F must remain bounded in the limit as (x → 0) . (62) Therefore . lim(t ( the integral (62) is indefinite ) Substituting from (61) we get = (65) p F ( x, a ) x But we have that δG a[ x] 1 t t 1− a (( )) – t a = 0 K = lim(t (the integral (60) is indefinite ) Thus = lim (t → 0) Fx (at t ) = lim (t → 0) p this case (a=0.5) (56) will approach zero as (x → 0 ) and hence remains bounded . Now suppose that a< 0.5 .In this case we consider a as a parameter.Hence we have ∫ Let us compute t x 2a − 1 } (60) G a [x]= x dF t ∫ must remain bounded. Assume that a =0.5 .( remember that we are treating a as a given exponent )This value a =0.5 will guarantee that the quantity { (( ∫ → 0) Fx (at t) } - lim (t → 0) t (58) × (lim x → 0 = { F x(at p ) – lim (t p We conclude from (56) that the product 0 p p (57) Applying L 'Hospital ' rule we get (lim x → ( t is a very small positive number 0<t<p) (t is the same small positive number 0<t<p) δx 0) (64) t is bounded . First we compute (lim x → → 0) ∫ Fdx t ( the integral (52) is indefinite) Since G[F] is bounded across the elementary interval [0,p], δ G[F] is bounded across this interval (53) From (52) we conclude that Ρ ( the integral (63) is indefinite ) We return to (49) and write lim (x (63) 1 (( )) − x 2 a −1 → 0) x a x (71) must remain bounded WCECS 2010 Proceedings of the World Congress on Engineering and Computer Science 2010 Vol I WCECS 2010, October 20-22, 2010, San Francisco, USA But 1 (( )) − x 2 a −1 x lim(x → 0 ) = lim(x → 0 ) xa 1 (( )) − x 2 a −1 1− 2 a x × x a 1− 2 a x x 1 x1− 2 a (( )) − 1 x = lim(x → 0 ) x1− a −1 = lim(x → 0 ) 1−a x (72) 1 ( − 2) a lim(a → 0.5) (x → 0) x 1− a (0.5 + x) −1 − 2 = lim (x → 0) x 0.5− x (0.5 + x) −1 − 2 = lim (x → 0) x 0.5 × x − x (0.5 + x) −1 − 2 = lim (x → 0) x 0.5 −x ( Since lim (x → 0) x =1) (80) It is evident that this last limit is unbounded. This contradicts our conclusion (71) that lim (x ) 1 (( )) − x 2 a −1 → 0) x a x must remain bounded (for a< 0.5 Therefore the case a<0.5 is rejected .We verify here that ,for a = 0.5 (71) remains bounded as (x → 0 ) . We have that 1 (( )) − x 2 a −1 x < 1- x 2 a −1 (73) We must apply L 'Hospital ' rule lim (x → 0) (0.5 + x) −1 − 2 = lim (x → 0) − (0.5 + x) −2 0.5 x −0.5 = lim (x → 0) − 2 × x 0.5 (0.5 + x ) 2 Therefore lim(a (x → 0.5) (x → 0) 1 (( )) − x 2 a −1 → 0) x a x < lim(a → 0.5) 1 − x 2 a −1 xa (74) We consider the limit lim(a → 0.5) (x → 0) We write a = (lim x → Hence we get lim(a 1 − x 2 a −1 xa (75) 0 ) ( 0.5 + x ) → 0.5) (x → 0) x 2 a −1 (76) = lim (x → 0) x → 0) x 2 x = 1 x (Since lim(x → 0) x = 1) =lim (x 2 ( 0.5 + x ) −1 (81) x 0.5 =0 Thus we have verified here that ,for a = 0.5 (71) approaches zero as (x → 0 ) and hence remains bounded. We consider the case a >0.5 . This case is also rejected, since according to the functional equation, if ( ζ (s ) =0) (s = a+ bi) has a root with a>0.5 ,then it must have another root with another value of a < 0.5 . But we have already rejected the case with a<0.5 Thus we are left with the only possible value of a which is a = 0.5 Therefore a = 0.5 This proves the Riemann Hypothesis . (77) References [1] E. C. Titchmarch, The Theory of the Riemann zeta – function. London: Oxford University Press, 1999, pp.13-14. Therefore we must apply L 'Hospital ' rule with respect to x in the [2] T. M. Apostol, Mathematical Analysis. Reading, limiting process (75) Massachusetts: Addison – Wesley Publishing Company, 1 − x 2 a −1 1974, pp. 76 – 77, pp. 391 –396. = lim(a → 0.5) lim(a → 0.5) (x → 0) [3] H. M. Edwards, Riemann's zeta function. New York: xa Academic Press Inc., 1974, pp. 37-38. − (2a − 1) x 2 a − 2 [4] T. M. Apostol, Introduction to Analytic Number Theory. (78) (x → 0) ax a −1 New York: Springer – Verlag, 1976, pp. 249 – 273. [5] N. Koblitz, P-adic Numbers P-adic Analysis, and Zeta1 ( − 2) Functions. New York: Springer – Verlag, 1984, pp. 109 – a = lim(a → 0.5) (x → 0) 128. x 1− a [6] W. Geiner, and J. Reinhardt, Field Quantization. Berlin: Now we write again Springer – Verlage, 1996, pp. 37-39. a = (lim x → 0 ) ( 0.5 + x ) (79) Thus the limit (78) becomes ISBN: 978-988-17012-0-6 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online) WCECS 2010
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