We report experimental response functions at twelve gamma-ray energies over the range of 123.6 keV to 11.67 MeV for a 2.54-cm-diameter x 2.54- cm-long and a 7.62-cm-diameter x 7.62-cm long bismuth germanate scintillation detector. The measurements were made at, or corrected to correspond to, source- to-detector distances of 100 cm. The resolutions of the detectors at a gamma-ray energy of 661.6 keV are 11.6 percent for the small detector and 13.0 percent for the large detector.