Source material for Agnes of Sorrento was culled from her observations of and experiences in Italy, collected during her third trip to Europe, which she took with her family.
『ソレントのアグネス』の材料はイタリアの観察と経験から抜粋したものであり、家族と共に行った3回目のヨーロッパ旅行で集めていた。