The existence and approximation of the periodic solutions for system of first order nonlinear differential equations by using lebesgue integrable
By: Butris, Rad N.; Aziz, Mirnah Adil. al-Tarbiyah wa-al-Ilm : Majallat ilmiyah lil-Buhuth al-Ilmiyah al-Asasiyah. Vol. 21, no. 1 (Mar. 2008), pp.61-77, 17 p.
Subjects: Differential equations