by University of Colorado (Boulder campus)

1879

by University of Colorado

1927

by University of Colorado

1897

by University of Colorado Boulder

1922

by University of Colorado Boulder

1928

by United States. National Aeronautics and Space Administration. Office of University Affairs

1968

by United States. National Aeronautics and Space Administration. Office of University Affairs

1969

by University of Illinois (Urbana-Champaign campus). Engineering Experiment Station

1927

by University of Colorado Boulder

1906

by University of Colorado (Boulder campus)

1905

by University of Colorado (Boulder campus)

1912

by Colorado. University

1907