Huernia piersii N.E.Br.

@book{de2007stapeliads,

title = {Stapeliads of southern Africa and Madagascar, Peter V. Bruyns, Umdaus Press, Hatfield, 600 pp in 2 Hard Cover Volumes, ISBN 1-919766-37-5 and-38-3, R1400-00, Email: umdaus@ succulents. net},

author = {AT De Villiers},

year  = {2007},

date = {2007-01-01},

urldate = {2007-01-01},

publisher = {Elsevier},

keywords = {},

pubstate = {published},

tppubtype = {book}

}

@book{germishuizen2003plants,

title = {Plants of southern Africa: an annotated checklist},

author = {Gerrit Germishuizen and NL2003 Meyer and others},

year  = {2003},

date = {2003-01-01},

urldate = {2003-01-01},

volume = {14},

publisher = {National Botanical Institute Pretoria},

keywords = {},

pubstate = {published},

tppubtype = {book}

}

@book{albers2002illustrated,

title = {Illustrated Handbook of Succulent Plants: Asclepiadaceae: Asclepiadaceae},

author = {Focke Albers and Ulrich Meve},

year  = {2002},

date = {2002-01-01},

urldate = {2002-01-01},

volume = {4},

publisher = {Springer Science \& Business Media},

keywords = {},

pubstate = {published},

tppubtype = {book}

}