Schemm-Gregory M. A new species of Filispirifer (Brachiopoda: Delthyridoidea) from the Dra Valley, Morocco (Lower Devonian). Zootaxa [Internet]. 2008 Apr. 2 [cited 2025 Apr. 30];1739(1):53–68. Available from: https://mapress.com/zt/article/view/zootaxa.1739.1.4