Diet Differentiation in Polymorphic Arctic Charr in Thingvallavatn, Iceland Malmquist, H. J. ; Snorrason, S. S. ; Skulason, S. ; Jonsson, B. ; Sandlund, O. T. ; Jonasson, P. M. Abstract Publication: Journal of Animal Ecology Pub Date: February 1992 DOI: 10.2307/5505 Bibcode: 1992JAnEc..61...21M