APA
The Royal Horticultural Society, . (1949). The rhododendron year book 1949 no.4. : The Royal Horticultural Society.
Chicago
The Royal Horticultural Society, . 1949. The rhododendron year book 1949 no.4. : The Royal Horticultural Society.
Harvard
The Royal Horticultural Society, . (1949). The rhododendron year book 1949 no.4. : The Royal Horticultural Society.
MLA
The Royal Horticultural Society, . The rhododendron year book 1949 no.4. : The Royal Horticultural Society. 1949.
