F.K.A.E.J. de Thümen [1-750, plus extras]

University of Illinois Herbarium
Catalog #: ILL00085411
s.n.
Phacidium trigonum J.C. Schmidt

USDA United States National Fungus Collections
Catalog #: BPI 1034049
s.n.
Phacidium trigonum Thüm.

University of Nebraska State Museum, C.E. Bessey Herbarium - Fungi
Catalog #: NEB00063060
A. Fr. Moller s.n. 00 April 1879
Phacidium trigonum J.C. Schmidt
Portugal, bei Coimbra