Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 40-68

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 69-85

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 159-195

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 196-203

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 267-284

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 305-318

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 479-485

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 523-585

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 614-648

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 649-665

Published in Journal of the Arnold Arboretum, in 1971, in volume 52, pages 691-694

Published in Journal of The Arnold Arboretum, in 1971, in volume 52, issue 1, pages 1-39

Published in Journal of The Arnold Arboretum, in 1971, in volume 52, issue 1, pages 86-109

Published in Journal of The Arnold Arboretum, in 1971, in volume 52, issue 1, pages 110-136

Published in Journal of The Arnold Arboretum, in 1971, in volume 52, issue 1, pages 137-158