A hand-list of the birds of the Philippine IslandsRichard Crittenden McGregor · First published 1906Open the Tome
Birds from Mindoro and small adjacent islandsRichard Crittenden McGregor · First published 1905Open the Tome
Birds from the islands of Romblon, Sibuyan, and Cresta de GalloRichard Crittenden McGregor · First published 1905Open the Tome
I. Birds from Mindoro and small adjacent islands. II. Notes on three rare Luzon birdsRichard Crittenden McGregor · First published 1905Open the Tome
On birds from Luzon, Mindoro, Masbate, Ticao, Cuyo, Culion, Cagayan Sulu, and PalawanRichard Crittenden McGregor · First published 1903Open the Tome
A list of the land birds of Santa Cruz County, CaliforniaRichard Crittenden McGregor · First published 1901Open the Tome
