@article{https://resolver.caltech.edu/CaltechAUTHORS:HEApnas61a, title = "The effects of pressure on the buoyant behavior of deoxyribonucleic acid and tobacco mosaic virus in a density gradient at equilibrium in the ultracentrifuge", journal = "Proceedings of the National Academy of Sciences of the United States of America", year = "1961", url = "https://resolver.caltech.edu/CaltechAUTHORS:HEApnas61a", id = "record", issn = "0027-8424", doi = "10.1073/pnas.47.7.1015", volume = "47" } @article{https://resolver.caltech.edu/CaltechAUTHORS:HEApnas61b, title = "A three-component theory of sedimentation equilibrium in a density gradient", journal = "Proceedings of the National Academy of Sciences of the United States of America", year = "1961", url = "https://resolver.caltech.edu/CaltechAUTHORS:HEApnas61b", id = "record", issn = "0027-8424", doi = "10.1073/pnas.47.7.999", volume = "47" }