Widmer, Molly. 1991. Human management of some useful plants gathered in Northeast Thailand. Oregon:University of Oregon;
Widmer, Molly. (1991) Human management of some useful plants gathered in Northeast Thailand (รายงานผลงานวิจัย). University of Oregon:Oregon.
Widmer, Molly. Human management of some useful plants gathered in Northeast Thailand. Oregon:University of Oregon, 1991.
Widmer, Molly. (1991) Human management of some useful plants gathered in Northeast Thailand (รายงานผลงานวิจัย). University of Oregon:Oregon.