Book  (1988)  Page(s) 172.  
 
location 128/1, R. setigera Michx. var. serena Palm. & Steyerm., 1924, bushy, 0.8 + 1 m, without prickles, light green medium size foliage

Book  (1976)  Page(s) 118.  
 
R. setigera....f. serena Palm. et Steyerm. - without prickles, foliage pubescent.

Book  (1940)  Page(s) 446.  
 
R. setigera....R. s. serena Palm. & Steyerm. var. Stems unarmed: lvs. pubescent beneath. Intr. 1924.