Website/Catalog  (1910)  Page(s) 11.  
 
Single Herbaceous Peonies
32—Apollo. Purple-rose; medium height; mid-season...25¢

Website/Catalog  (1909)  Page(s) 9.  
 
JAPANESE VARIETIES. The following varieties are others’ introduction.
Apollo, pink guards and golden center ...$ .75

Book  (Apr 1907)  Page(s) 25.  
 
166. APOLLO, P
(1) 1904, Harrison's Peony Manual p. 53

Book  (1907)  Page(s) 49.  
 
Japanese Peonies...
Apollo. Deep pink, shading lighter toward the edges.

Website/Catalog  (1895)  Page(s) [2].  
 
Single Herbaceous Pæonies.
Fifty cents each, except as priced. Twelve varieties, our selection $5.00.
Some of the new single pæonies are even more beautiful than the double ones; being very delicate, they are most suitable as cut-flowers, and generally bloom quite early; below are some of the best varieties available.
Apollo, deep rose.

Website/Catalog  (1890)  Page(s) 28.  
 
Single Herbaceous Pæonies.
Apollo, purple-rose. [K]