Stewart, F. H. (September 1942). "Chemical data on a silica-poor argillaceous hornfels and its constituent minerals". Mineralogical Magazine and Journal of the Mineralogical Society. 26 (178): 260–266. Bibcode:1942MinM...26..260S. doi:10.1180/minmag.1942.026.178.04.
Stewart, F. H. (September 1942). "Chemical data on a silica-poor argillaceous hornfels and its constituent minerals". Mineralogical Magazine and Journal of the Mineralogical Society. 26 (178): 260–266. Bibcode:1942MinM...26..260S. doi:10.1180/minmag.1942.026.178.04.