中国科学技术信息研究所--国家工程技术数字图书馆

university of washington.(11)

arizona state university.(5)

purdue university.(5)

rutgers the state university of new jersey - new brunswick.(5)

the university of wisconsin - madison.(5)

university of maryland college park.(5)

university of toronto (canada).(5)

iowa state university.(4)

tufts university(4)

colorado state university.(3)

state university of new york college of environmental science and forestry.(3)

the ohio state university(3)

the university of arizona.(3)

tufts university.(3)

cornell university(2)

kansas state university.(2)

michigan state university.(2)

northern illinois university.(2)

purdue university(2)

rutgers the state university of new jersey school of graduate studies.(2)

southern illinois university at carbondale.(2)

southern university and agricultural and mechanical college.(2)

syracuse university.(2)

the university of wisconsin - madison(2)

trent university (canada).(2)

university of california berkeley(2)

university of california berkeley.(2)

university of california davis.(2)

university of california los angeles.(2)

university of california santa barbara.(2)