Senowbari-Daryan, Baba, in Rucha Ingavat-Helmcke. „Sponge assemblage of some Upper Permian reef limestones from Phrae province (Northern Thailand)“. Geologija, let. 36, št. 1, december 1993, str. 5-59, https://doi.org/10.5474/geologija.1994.001.