Jois, Seetharama DS and Easwaran, KRK and Bednarek, Maria and Blout, ER (1992) Conformational and Ion Binding Properties of a Cyclic Octapeptide, $cyclo(Ala-Leu-Pro-Gly)_2$. In: Biopolymers, 32 (8). pp. 993-1001.