Sawyer, W.H. & Baxter, J.W. & Manning, M. & Heinicke, E. & Perks, A.M. (1970)
A fraction resembling oxytocin from Squalus acanthias: pharmacological comparisons with synthetic peptides. General and Comparative Endocrinology, 15(1), 52–58
DOI: 10.1016/0016-6480(70)90096-1

Sawyer, W.H. & Manning, M. & Heinicke, E. & Perks, A.M. (1969)
Elasmobranch oxytocin-like principles: Comparisons with synthetic glumitocin. General and Comparative Endocrinology, 12(2), 387–390
DOI: 10.1016/0016-6480(69)90212-3

Sawyer, W.H. & Freer, R.J. & Tseng, T.-C. (1967)
Characterization of a principle resembling oxytocin in the pituitary of the holocephalian ratfish (Hydrolagus colliei) by partition chromatography on Sephadex columns. General and Comparative Endocrinology, 9(1), 31–37
DOI: 10.1016/0016-6480(67)90094-9

Sawyer, W.H. (1967)
Chromatographic and pharmacological characteristics of the active neurohypophysial principles of the spiny dogfish Squalus acanthias. General and Comparative Endocrinology, 9(2), 303–311
DOI: 10.1016/0016-6480(67)90065-2

Perks, A.M. & Sawyer, W.H. (1965)
A New Neurohypophyseal Principle in an Elasmobranch, Raia ocellata. Nature, 205(4967), 154–156
DOI: 10.1038/205154a0

Sawyer, W.H. (1965)
Active neurohypophysial principles from a cyclostome (Petromyzon marinus) and two cartilaginous fishes (Squalus acanthias and Hydrolagus collei). General and Comparative Endocrinology, 5(4), 427–439
DOI: 10.1016/0016-6480(65)90103-6