text: A number of studies have delineated in DAFC-66D the 320bp Amplification
  Control Element on the third chromosome, ACE3, required for high levels of amplification (Figure 3C) (de Cicco and Spradling, 1984; Delidakis and Kafatos, 1989; Orr-Weaver et al., 1989; Orr-Weaver and Spradling, 1986).