THE RELATIONSHIPS OF THE AMERICAN BLACK-FRUITED HAWTHORNS CRATAEGUS ERYTHROPODA, C. RIVULARIS, C. SALIGNA AND C. BRACHYACANTHA TO C. SER. DOUGLASIANAE (ROSACEAE)
Published in Sida, Contributions To Botany, in 1999, in volume 18, issue 3, pages 647-660
Date published:1999