Earliest:

       I used to work in Chicago --
                I used to but no more.
        I used to work in Chicago,
                In a hosiery store.
        A lady asked for some garters,
                I asked the kind she wore:
        "Rubber," she said. Rubber I did.
                I did – but not any more.
                
From "National Lithographer," Vol. 30 (1923).

Also in "The Squib" (Massachusetts Agricultural College [now U. of Massachusetts, Amherst]), likewise 1923.