Allison, M., O’Leary, S., Lindley, M., Crane, L., Hurley, L., Beaty, B., … Kempe, A. (1969). Financing of Vaccine Delivery in Primary Care Practices. Academic Pediatrics, 17(7), 770-777. https://doi.org/10.1016/j.acap.2017.06.001 (Original work published 1969)