Moults and sequence of plumages in the rock ptarmigan (Lapopus mutus (Montin)) /
Salomonsen, Finn,1909-
Copenhagen : P. Haase & søn,
1939.
"Reprinted from Videnskabelige meddelelser fra Dansk  naturhistorisk forening, vol. 103."
"Dansk oversigt": p. [457]-491.
Afhandling--Copenhagen.
"Literature": p. [440]-456.
Rock ptarmigan.
Feathers.