@article{https://resolver.caltech.edu/CaltechAUTHORS:20151211-113308787, title = "Galaxy M 31", journal = "Science", year = "1964", url = "https://resolver.caltech.edu/CaltechAUTHORS:20151211-113308787", id = "record", issn = "0036-8075", doi = "10.1126/science.145.3635.952", volume = "145" }