"Montanari's greatest achievements, however, were in astronomy, particularly in his observations of the star Algol, which contributed to one of the earliest and most important chapters in the history of astrophysics, the study of the variable stars." (DSB)
Montanari's paper reporting his observations on variable stars was printed in Prose de' signori accademici galati, Bologna 1671, edited by Vittorio Zani, where it is paginated 369-92. In this copy the text is paginated 1-22 but the plates retain the original pagination.