The Fotostiftung Schweiz has had a significant collection of work by Roman Vishniac dating from 1983 when they hosted a major exhibition of Vishniac's work. There are approximately 253 works in the Vishniac collection.
Fotostiftung Schweiz
Grüzenstrasse 45
CH-8400 Winterthur (Zürich)
Telephone +41 52 234 10 30
Fax +41 52 234 10 40
Infoline +41 (0)52 234 10 34
Email info@fotostiftung.ch
http://www.fotostiftung.ch/en/