Air Photo Evidence and the Ball Report

Kharga Oasis

Central Alps, Including the Bernese Oberland, and All Switzerland Excepting the Neighbourhood of Monte Rosa and the Great St. Bernard

Contribution to the Flora of North Patagonia and the Adjoining Territory

A Guide to the Western Alps

Cool Cottontail

Understanding disease

Miss One Thousand Spring Blossoms

In the heat of the night

Styrian, Carnic and Julian Alps

Contributions to the Flora of the Peruvian Andes