…italianos though candidly he was none the less free to admit those icecreamers and friers in the fish way not to mention the chip potato variety and so forth over in little Italy there near the Coombe were sober thrifty hardworking fellows except perhaps a bit too given to pothunting the harmless necessary animal of the feline persuasion of others at night so as to have a good old succulent tuckin with garlic de rigueur off him or her next day on the quiet and, he added, on the cheap.
There are no more uses of "de rigueur" in the book.
Show samples from other sources
Everyone has subjects of conversation, ladies for instance…. people in high society always have their subjects of conversation, c’est de rigueur, but people of the middle sort like us, thinking people that is, are always tongue-tied and awkward.
Fyodor Dostoyevsky -- Crime and Punishment
He mailed it in an envelope with the mourning vignettes that were de rigueur for a letter to a recent widow, and with no return address on the back.
Gabriel Garcia Marquez -- Love in the Time of Cholera