Earth Space ScienceEllsworth S. obourn, Elwood D. Heiss, Margaret Mck. Lawler and Gaylord C. Montgomery · First published 1972Open the Tome
Teaching the pursuit of scienceWoodburn, John H. Obourn, Ellsworth S. · First published 1965Open the Tome
Analysis of research in the teaching of science, July 1956-July 1957Ellsworth S. Obourn · First published 1959Open the Tome
Analysis of research in the teaching of science, July 1955-July 1956Ellsworth S. Obourn · First published 1958Open the Tome
Analysis and check list on the problem solving objectiveEllsworth S. Obourn · First published 1956Open the Tome
Instructional tests in physicsEarl Rouse Glenn, Ellsworth S. Obourn · First published 1942Open the Tome
