Margherita Colonna
She was born in Palestrina about 1255. Her father, Oddone Colonna, died when she was about two years old. Her mother, who was also named Margherita and who was the sister of Matteo Rosso Orsini and a pious woman, died when Margherita was probably a little over ten years old. Margherita was left in the care of her older brothers.
Knud Jeppesen
Jeppesen's name is invariably associated with the study of musical counterpoint, particularly in the style of Palestrina, of whom he was the leading scholar of his day. His 1930 work "Counterpoint: The Polyphonic Vocal Style of the Sixteenth Century" has been a standard textbook since its appearance in German (1935) and English (1939), and remains in print today (the third and final edition remains untranslated). His doctoral thesis was expanded in 1923 and appeared in English in 1927 as "The Style of Palestrina and the Dissonance" – a work which "The New Grove" cites as being the "most distinguished and influential example of stylistic analysis at this time".