Catanzariti, R. and Perilli, N. (2006) “AGE OF THE OTTONE UNIT IN THE ZIGNAGO AREA (EXTERNAL LIGURIAN UNITS, NORTHERN APENNINES): CONSTRAINTS FROM CALCAREOUS NANNOFOSSILS”, Ofioliti, 31(1), pp. 11-24. doi: 10.4454/ofioliti.v31i1.324.