Porte, William S. (William Solomon), 1891-. Commercial production of greenhouse tomatoes.. Washington, D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc3366/. Accessed May 21, 2013.
Porte, William S. (William Solomon), 1891-. Commercial production of greenhouse tomatoes.. Washington, D.C.. UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc3366/. Accessed May 21, 2013.