Incoming Resources
- Garrard Pub. Co., Champaign, Ill., 1966
- Illinois Natural History Survey, Champaign, Ill., 2001
- Sagamore Pub., Champaign, Ill., c1995
- SP, L.L.C., Champaign, Ill., c2001
- Garrard Pub. Co., Champaign, Ill., c1981
- Garrard Pub. Co., Champaign, Ill., 1974