Perdeck A.C. (1963) Does navigation without visual clues exist in Robins? ARDEA 51 (2-4): 91-104

Three Robins tested during spring migration in a Kramer-cage indoors, with all visual clues excluded, moved at random in the cage during their nightly period of migratory restlessness. This result is in contrast with the claim of Fromme (1961) that Robins can orient in a similar situation.