1. Anderson, N.H. and Wold, J.L., Can. Ent. 104: 189–201, 1972.
2. Blickle, R.L., N.H. Agric. Exper. Sta. Bull. 509, Durham, 1979.
3. Canton, S.P., Ward, J.V., U.S. EPA Environ. Res. Lab. Duluth, 1978.
4. Denning, D.G., Bull. Brook. Ent. Soc. 42: 145–148, 1947.
5. Denning, D.G., Amer. Midl. Nat. 42: 112–122, 1949.