1. J. Abdeljaoued, 1997
2. Greatest common divisor of several polynomials;Barnett;Proc. Camb. Phil. Soc.,1971
3. Symbolic Integration I. Transcendental Functions;Bronstein,1997
4. Quantifier elimination for real closed fields by cylindrical algebraic decomposition;Collins,1975
5. G. Diaz-Toca, L. Gonzalez-Vega