by Freeman C.E, Worthington R.D, Jackson M.S
Published in Biotropica (01.12.1991)

by Freeman, C.E, Wilken, D.H
Published in American journal of botany (01.11.1987)

by Stiles, F.G, Freeman, C.E
Published in Biotropica (01.06.1993)

by Petit, Sophie, Freeman, C. Edward
Published in Biotropica (01.06.1997)

by Freeman, C.E. (University of Texas at El Paso, TX), Worthington, R.D
Published in Biotropica (01.09.1989)

by Freeman, C.E. (University of Texas at El Paso, El Paso, TX), Head, K.C
Published in The Southwestern naturalist (01.12.1990)

by Freeman, C.E, Reid, W.H, Worthington, R.D
Published in American journal of botany (01.11.1985)

by Elisens, W.J, Freeman, C.E
Published in American journal of botany (01.07.1988)

by Lammers, T.G, Freeman, C.E
Published in American journal of botany (01.11.1986)

by Freeman, C.E, Worthington, R.D, Corral, R.D
Published in Biotropica (01.01.1985)

by Walters, J.P, Freeman, C.E
Published in The Southwestern naturalist (19.08.1983)

by Freeman, C.E, Worthington, R.D
Published in Madroño (01.04.1985)

by Reid W.H, Freeman C.E, Echlin R.D
Published in The Southwestern naturalist (21.02.1981)

by Freeman C.E, Reid W.H, Becvar J.E, Scogin R
Published in Botanical gazette (Chicago, Ill.) (01.03.1984)

by Chrystian Tejedor, Anthony Man and Jennifer Peltz Staff Writers Staff Writers Leon Fooksman, Marc Freeman, Diane C. Lade and Edward Sifuentes contributed to this report
Published in Sun-sentinel (Fort Lauderdale, Fla.) (03.11.2005)