@article{article361e8d96,
title   = {K-feldspars from the Poços de Caldas nepheline syenites, Southern Brazil: chemical, optical and XRD studies},
author = {Ulbrich, Mabel N. C. and Rocha-Campos, A. C.},
year = {1986},
journal   = {Anais Academia Brasileira de Ciências}
}