University of Pittsburgh, Department of Physics and Astronomy, Allegheny Observatory, History of Allegheny Observatory
http://www.pitt.edu/~aobsvtry/history.html
Referenced in:
Allegheny Observatory
University of Pittsburgh, Department of Physics and Astronomy, Allegheny Observatory, History of Allegheny Observatory
http://www.pitt.edu/~aobsvtry/history.html
Referenced in:
Allegheny Observatory