Douglas Gunn...[et al.] Douglas Gunn...[et al. Douglas Ehninger,... [et al.] Douglas A.Downing...[et al.] Douglas Ehninger,... [et al. Susan Cain...[et al.] Douglas A.Downing...[et al. by Douglas Biber...[et al.] by Douglas Pancoast...[et al.] Douglas A. Bernstein,...[et al.]