Verbatim text: Werth, C. R. 1991. Isozyme studies on the Dryopteris "spinulosa" complex. I: The origin of the log fern Dryopteris celsa. Syst. Bot. 16(3): 446--461.
Author: Werth, C.R.
Year: 1991
Title: Isozyme studies on the Dryopteris "spinulosa" complex. I: The origin of the log fern Dryopteris celsa
Journal: Syst. Bot
Volume: 16
Pages: 446–461