1. L.G. Helper and C. His, AOSTRA Technical Publication Series #6, 1989, Edmonton, AB.
2. J. Oxenford, J. Coward and S. Bulatovic, CIM Annual General Meeting, April 30— May 2, 2001, Quebec City.
3. L.G. Helper and R.G. Smith, AOSTRA Technical Publication Series #14, 1994, Edmonton, AB.