http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
unter Mitwirkung von H. Diels und K. Holl in Berlin hrsg. von Otto Leuze.
Volumes 1-2 contain essays on philosophical, volume 3 on religious subjects.
Volume 3 includes a memorial address by H. Diels, and a list of Zeller's writings.