Collins, Holden & Setchell, Phycoth. Bor.-Amer.
Collins, F.S.; Holden, I.; Setchell, W.A. [1-2300]

Brown University - Algae
Catalog #: ABRU00003885
W. J. V. Osterhout s.n.
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Berkeley, CA

University of Michigan
Catalog #: 735954
W.J.V. Osterhout #s.n. 00 July 1902
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Alameda, Berkeley

University of Michigan
Catalog #: 735958
W.J.V. Osterhout #s.n. 00 July 1902
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Alameda, Berkeley

Michigan State University Algae
Catalog #: MSC0182033
W.J.V. Osterhout #s.n. 00 July 1902
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Alameda, Berkeley

Miami University - Algae
Catalog #: 000188165
W.J.V. Osterhout #s.n. 00 July 1902
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Alameda, Berkeley

Drexel University, Academy of Natural Sciences - Algae
Catalog #: PH00142581
911dff4a-bc83-4239-9bb6-36cc068d2686
W.J.V. Osterhout; N.L. Gardner #s.n. 00 July 1902
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Alameda, Berkeley

Yale University Herbarium
Catalog #: YU.092254
Winthrop John Vanleuven Osterhout s.n.
Closterium acerosum Ehrenberg ex Ralfs
United States, California, Alameda, Berkeley; Berkeley, CA