3 literature references for Anser albifrons Hartlaub, 1852:

Author: Mayr, Ernst, and G. William Cottrell, eds.
Year: 1979
Title:
Source: Check-List of Birds of the World, vol. 1, Second Edition
Author: Dickinson, Edward C., ed.
Year: 2003
Title:
Source: The Howard and Moore Complete Checklist of the Birds of the World, 3rd edition
Author:
Year: 2006
Title:
Source: website, Zoonomen - Zoological Nomenclature Resource, 2006.12.10