APA

Ritter W. E., . (1913). The simple ascidians from the northeastern Pacific in the collection of the United States National Museum. Washington: Government Printing Office.

Chicago

Ritter William Emerson, . 1913. The simple ascidians from the northeastern Pacific in the collection of the United States National Museum. Washington: Government Printing Office.

Harvard

Ritter W. E., . (1913). The simple ascidians from the northeastern Pacific in the collection of the United States National Museum. Washington: Government Printing Office.

MLA

Ritter William Emerson, . The simple ascidians from the northeastern Pacific in the collection of the United States National Museum. Washington: Government Printing Office. 1913.