@article {k56,
	title = {Immunization against Poliomyelitis with Living Attenuated Virus},
	journal = {The American Journal of Tropical Medicine and Hygiene},
	volume = {5},
	number = {3},
	year = {1956},
	pages = {440-452},
	url = {https://www.ajtmh.org/content/journals/10.4269/ajtmh.1956.5.440},
	author = {Koprowski, H.}
}
