Roberts, A V <br/><br/>
Relationship between species in the genus   [electronic resource] 

 -  Botanical journal of the Linnean Society. Linnean Society of London  Jun 1977 
 - 309-328 p.  digital 
<br/><br/> Publication Type: Journal Article 
<br/><br/><label>ISSN: </label>0024-4074 
<br/><br/><label>Standard No.: </label>10.1111/j.1095-8339.1977.tb01184.x  doi