A zillion or so years ago (mid-1970s) H. Scott Gordon wrote a paper called, appropriately, "Why Did Marshall Transpose the Axis?" As you might guess the argument was basically because of the welfare-economics motivations and the relationship between quantity and marginal utility. Since quantity is the independent variable in a marginal utility function it should be on the horizontal axis, as it should for the demand curve relating quantity to demand price. The paper was certainly undergraduate accessible, but unfortunately I do not think it was ever published and it was pre-electronic. I think I still have a hard copy somewhere if you want me to send it to you. D. Wade Hands