Chemical essays.

MLA

Watson, Richard and Edgar Fahs Smith Memorial Collection (University of Pennsylvania). Chemical essays. London, [publisher not identified], 1783-91.

APA

Watson, R. & Edgar Fahs Smith Memorial Collection (University of Pennsylvania). (1783). Chemical essays. London, [publisher not identified].

Chicago

Watson, Richard and Edgar Fahs Smith Memorial Collection (University of Pennsylvania). Chemical essays. London, [publisher not identified], 1783-91.