@other{https://resolver.caltech.edu/CaltechTHESIS:04112011-104242807, title = "Comparison of the properties of cholinergic differentiation factors and examination of their possible role in vivo", year = "1991", url = "https://resolver.caltech.edu/CaltechTHESIS:04112011-104242807", id = "record", doi = "10.7907/9ffk-0t58" }