1. Klin Monatsbl Augenheilkd 1877; 15: 99. Cited in: Duke-Elder S. System of ophthalmology;Steinheim,1973
2. Congenital absence of the inferior rectus muscle;Cooper, E.L.; Milk, R.O.; Greenspan, J.A.;Arch Ophthalmol,1971
3. Arch Oftalmol B Aires 1929; 4;Natale
4. Congenital absence of inferior and external rectus muscles;Walker, J.P.S.;BrJ Ophthalmol,1954
5. Anomalies of the eye muscles;Posey, W.C.;Trans Am Acad Ophthalmol Otolaryngol,1924