『Abstract
　Least-squares analyses of powder X-ray diffraction data have been undertaken for minerals and synthetics of composition (Mg,Mn,Fe,Co,Ni)3-xSi2O5(OH)4. New polytypes of nepouite and greenalite have been established, and eleven new or altered unit cells have been calculated. Baumite is an unnecessary varietal name for a manganoan ferroan lizardite-1T; tosalite is an unnecessary varietal name for a manganoan greenalite; clinochrysotile is an unnecessary polytype name for chrysotile-2Mc1; orthochrysotile is an unnecessary polytype for chrysotile-2Orc1; ortho-antigorite and ortho-hexagonal serpentine are unnecessary names for lizardite-6T1; and septechlorite should not be used. The powder data of the serpentine group are in general, poor.』

（Introduction）
Mg3Si2O5(OH)4
Ni3Si2O5(OH)4
Mn3-xSi2O5(OH)4
Fe3-xSi2O5(OH)4
Co3Si2O5(OH)4
Group name
Acknowledgements
References