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by Hacker, Barton C.
by Tucker, Jennifer; Hacker, Barton C.; Vining, Margaret
by National Aeronautics and Space Administration; Grimwood, James M.; Hacker, Barton C.; et al.
by National Aeronautics and Space Administration; Hacker, Barton C.; Grimwood, James M.
by Hacker, Barton C.; Grimwood, James M.; National Aeronautics and Space Administration
by Hacker, Barton C.; Vining, Margaret
by Barton C. Hacker & Margaret Vining
by Vining, Margaret; Hacker, Barton C.