R. Hekman

Social stimulation, nuptial colouration, androgens and immunocompetence in a sexual dimorphic cichlid fish

T. Groothuis, R. Schulz, P. Dijkstra, 2007, Behavioral Ecology and Sociobiology.

Experimental global food reduction raises resource acquisition costs of brood care helpers and reduces their helping effort

M. Taborsky, R. Bruintjes, R. Hekman, 2010 .