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The infrared-absorption spectra of accepters confined in the center of GaAs/A1(x)Ga(1-x)As quantum wells in the presence of an external magnetic field have been calculated. The calculations are based on a four-band effective-mass theory in which the valence-band mixing as well as the mismatch of the band parameters and the dielectric constants between well and barrier materials have been taken into account. The dipole transition rule is assumed for the infrared absorption. The oscillator strengths of allowed transitions between the acceptor ground states and excited states, corresponding to the transitions G, D, and C in bulk GaAs, are calculated for different well widths in the range 50-200 Angstrom with an external magnetic field up to 10 T. The oscillator strength of these infrared acceptor transitions exhibits a strong polarization dependence.