1. Diplopia
2. Accommodation and Convergence
3. Clinical Course and Management
4. Kramer, Mary Everist: Clinical Orthoptics: Diagnosis and Treatment, St. Louis, C. V. Mosby, 1949, (a) pp. 188–189; (b) p. 190; (c) p. 221; (d) p. 225; (e) pp. 242–244; (f) pp. 316–318.
5. Lancaster, Julia E.: A Manual of Orthoptics, Springfield, Ill., Charles C Thomas, 1951, (a) p. 16; (b) p. 94; (c) p. 95.