Graptolithina
Family

Cyclograptidae Bulman, 1938

https://files.geocollections.info/large/96/f6/96f64421-89b2-4f40-b334-a88264b9979e.jpghttps://files.geocollections.info/large/06/1b/061bb4f7-d0d0-4ade-a0a6-8d0ee9115866.jpg
Selection of related publications
Mierzejewski, P. 1978. Tuboid graptolites from erratic boulders of Poland. Acta Palaeontologica Polonica 23, 4, 557-574.
Bulman, O. M. B., Rickards, R. B. 1966. A Revision of Wiman's Dendroid and Tuboid Graptolites. Bulletin of the Geological Institutions of the University of Uppsala 43, 6-8, 1-72. University of Uppsala.
Skevington, D. 1963. Graptolites from the Ontikan Limestones (Ordovician) of Öland, Sweden. I: Dendroidea, Tuboidea, Camaroidea, and Stolonoidea. Bulletin of the Geological Institutions of the University of Uppsala 42, 1-62.
Obut, A. M. 1960. Correlation of some parts of Estonian Ordovician and Silurian deposits according to graptolites. ENSV TA Geoloogia Instituudi uurimused V, 143-157.
Obut, A. M. 1957. Kassifikaciâ i ukazatel' rodov graptolitov. Ežegodnik Vsesoûznogo Paleontologičeskogo Obŝestva XVI, 11-47. Gosudarstvennoe Nauchno-tehnicheskoe Izdatel'stvao Literatury po Geologi i Ohrane Hedr.