APA

Olson S. L., .Nature of the variability in the variable seedeater in Panama (<Sporophila americana: Emberizinae>). : .

Chicago

Olson Storrs L, .Nature of the variability in the variable seedeater in Panama (<Sporophila americana: Emberizinae>). : .

Harvard

Olson S. L., .Nature of the variability in the variable seedeater in Panama (<Sporophila americana: Emberizinae>). : .

MLA

Olson Storrs L, .: . .