Williamson, W. C. (1887). A monograph on the morphology and histology of Stigmaria ficoides. Printed for the Palæontographical society.
Chicago-viite (17. p.)Williamson, William Crawford. A Monograph on the Morphology and Histology of Stigmaria Ficoides. London: Printed for the Palæontographical society, 1887.
MLA-viite (8. p.)Williamson, William Crawford. A Monograph on the Morphology and Histology of Stigmaria Ficoides. Printed for the Palæontographical society, 1887.
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