[652] Kidston (02) pp. 358, 359.
[653] Tansley and Chick (01) p. 36.
[654] Kidston (05) p. 547.
[655] Renault (96) A.
[656] Weiss, F. E. (08).
[657] Browne (09) p. 25.
[658] Scott (02) uses the terms old and new wood in discussing the evolutionary sequence in plant steles.
[659] White (07).
[660] Bower (08) p. 305.
[661] Browne (09) p. 37.