Jepson ManualBruce G. Baldwin, Douglas H. Goldman, David J. Keil, Robert Patterson, Thomas J. Rosatti · First published 2012Open the Tome
Human society and the natural worldDavid V. J. Bell, Roger Keil, Gerda R. Wekerle, York University (Toronto, Ont.). Faculty of Environmental Studies · First published 1994Open the Tome
Vascular plant taxonomyDirk R. Walters, David J. Keil, Bonnie Walters, Zack E. Murrell · First published 1988Open the Tome
