Nicola Fusco, Paolo Marcellini, and Carlo Sbordone are legendary figures in Italian mathematics, particularly known for their rigorous approach to Analysis. Their textbooks and exercise sets are standard for STEM students across Italy.

from their syllabus, such as multiple integrals or differential equations? Lezioni di Analisi matematica due - Google Books

The "Fusco-Marcellini-Sbordone" series is known for balancing rigorous theoretical explanations with a vast array of solved problems.