TY  - JOUR
AU  - Burton, T.A.
TI  - Periodic Solutions by Picard's Approximations
JO  - Canadian mathematical bulletin
PY  - 1968
SP  - 743
EP  - 745
VL  - 11
IS  - 5
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1968-092-2/
DO  - 10.4153/CMB-1968-092-2
ID  - 10_4153_CMB_1968_092_2
ER  -