1. Lect. Notes Math.;R.W. Bruggeman,1981
2. Bruggeman, R.W.: Modular forms of varying weight. II. Math. Z.192, 297?328 (1986)
3. Bruggeman, R.W.: Modular forms of varying weight. III. J. Reine. Angew. Math.371, 144?190 (1986)
4. Lect. Notes Math.;D.A. Hejhal,1983
5. Lang, S.: Algebraic number theory. Reading, Mass.: Addison-Wesley 1970