1. The physiology and management of divergent strabismus;Costenbader,1950
2. Strabismus, Heterophoria, Ocular Motor Paralysis; Clinical Ocular Muscle Imbalance;Hugonnier,1969
3. An analysis of one hundred cases of divergent strabismus;Simpson;Trans Can Ophthalm Soc,1962
4. Statistics on deviations of binocular imbalance;Jonkers;Ophthalmologica,1960