Complex sentence: Grimaldi had the plans based on the Palazzo Farnese Histoire de Puyricard makes this claimmhowever it also attributes one of the Palazzo Farnese to Michaelangelo-who did not design a Palazzo Farnese.
Split into simpler sentences: Grimaldi had the plans based on the Palazzo Farnese Histoire de Puyricard makes this claim. However it also attributes one of the Palazzi Farnese to Michaelangelo-who did not design a Palazzo Farnese.