Published in Journal of The Arnold Arboretum, in 1955, in volume 36, issue 1, pages 110-114

Published in Journal of The Arnold Arboretum, in 1955, in volume 36, issue 1, pages 115-117

Published in Journal of The Arnold Arboretum, in 1955, in volume 36, issue 2/3, pages 165-170

Published in Journal of The Arnold Arboretum, in 1955, in volume 36, issue 2/3, pages 305-317

Published in Journal of The Arnold Arboretum, in 1955, in volume 36, issue 4, pages 431

Published in Journal of the Arnold Arboretum, in 1955, in volume 36, pages 52-109

Published in Journal of the Arnold Arboretum, in 1955, in volume 36, pages 209-239

Published in Journal of the Arnold Arboretum, in 1955, in volume 36, pages 397-401