Sehrbrock, Angelika Electron Microscopy and Analytics, Center of Advanced European Studies and Research (caesar), Max Planck Society;
https://www.schweizerbart.de/papers/ejm/detail/21/73658/Amorphous_calcium_carbonate_in_the_shell_material_of_the_brachiopod_Megerlia_truncata (Publisher version)
Griesshaber, E., Klem, K., Sehrbrock, A., Mader, W., Mutterlose, J., Brand, U., et al. (2009). Amorphous calcium carbonate in the shell material of the brachiopod Megerlia truncata. European Journal of Mineralogy, 21, 715-723. doi:10.1127/0935-1221/2009/0021-1950.