Penecontemporaneous syenitic-phonolitic and basic-ultrabasic-carbonatitic rocks at the Poços de Caldas alkaline massif, SE Brazil: geology and geochronologic evidence - Ulbrich, H.; Vlach, Silvio Roberto Farias; Ulbrich, Mabel N. C.; Kawashita, Koji (Revista Brasileira de Geociências, 2002)