References:

1. DeMay RM. The Art & Science of Cytopathology, 2nd ed. ASCP Press, 2012
2. Koss LG. Diagnostic Cytology and Its Histopathologic Bases, 3rd ed. J.B. Lippincott Company, 1979
3. Bibbo M. Comprehensive Cytopathology, 2nd ed. W.B. Saunders Company, 1997