1. Anderson, M., Rummel, J.A., Deutsch, S.: NASA Techn. Mem. n? 58217, 1 (1979)
2. Calendar, R., Lindahl, G.: Virology 39, 867 (1969)
3. Cogoli, A., Tschopp, A.: Adv. Biochem. Eng. 22, 1 (1982)
4. Hanahan, D.: J. Mol. Biol. 166, 577 (1983)
5. Maniatis, T., Fritsch, E.F., Sambrook, J.: Molecular cloning, a laboratory manual. Cold Spring Harbor Laboratory 1982