@article{SLC_1986_14_a1,
     author = {Don Rawlings},
     title = {The {ABC's} of {Classical} {Enumeration}},
     journal = {S\'eminaire lotharingien de combinatoire},
     publisher = {mathdoc},
     volume = {14},
     year = {1986},
     url = {http://geodesic.mathdoc.fr/item/SLC_1986_14_a1/}
}