Citation: P. Alvarez et al., OBRUCHEVELLA, A CYANOBACTERIUM FROM UPPER PROTEROZOIC OF CONGO - IMPLICATIONS IN THE PROBLEM OF AGE OF THE SCHISTO-CALCAIRE GROUP AND OF THE UPPER PROTEROZOIC GLACIATION, Comptes rendus de l'Academie des sciences. Serie II. Mecanique, physique, chimie, astronomie, 320(7), 1995, pp. 639-646