Ômura, H., Honda, K. & Hayashi, N. Identification of feeding attractants in oak sap for adults of two nymphalid butterflies, Kaniska canace and Vanessa indica. Physiol Entomol, 25, 281-287 (2000).
Fischer, K. & Fiedler, K. Resource-based territoriality in the butterfly Lycaena hippothoe and environmentally induced behavioural shifts. Anim Behav, 61, 723-732, doi:10.1006/anbe.2000.1662 (2001).