Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 1-44

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 45-61

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 63-128,

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 211-242

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 243-260

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 261-263

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 265-266

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 267-313

Published in Journal of the Arnold Arboretum, in 1981, in volume 62, pages 457-486

Published in Journal of The Arnold Arboretum, in 1981, in volume 62, issue 2, pages 129-209

Published in Journal of The Arnold Arboretum, in 1981, in volume 62, issue 4, pages 487-516

Published in Journal of The Arnold Arboretum, in 1981, in volume 62, issue 4, pages 517-540