Publication Type:Journal Article Year of Publication:1978 Authors:J. A. DíazGonzález, T.E.&GonzálezPrieto Journal:Rev. Fac. Ci. Univ. OviedoRev. Fac. Ci. Univ. Oviedo Volume:17-19 Pagination:303-308 Add new commentGoogle ScholarBibTeXRTFMARCEndNote XMLRIS