@book{10142,
	author = {Walker, Egbert H. and Ching, Ren Chang.},
	title = {Plants collected by R. C. Ching in southern Mongolia and Kansu Province, China.},
	publisher = {U.S. Govt. Print. Off.,},
	year = {1941.},
	series = {Smithsonian Institution.  U. S. National Museum.  Contributions from the U. S. National Herbarium,},
	address = {Washington,},
	note = {Issued July 22, 1941.}
}