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PMID 4116246 4116246 DOI 10.1016/s0140-6736(72)92164-2 10.1016/s0140-6736(72)92164-2
Cite this article
Weissmann, M. C., Foliaki, L., Billings, E. L., & Billings, J. J. (1972). A trial of the ovulation method of family planning in Tonga. *Lancet (London, England)*, *2*(7781), 813-816. https://doi.org/10.1016/s0140-6736(72)92164-2
Weissmann MC, Foliaki L, Billings EL, Billings JJ. A trial of the ovulation method of family planning in Tonga. Lancet. 1972;2(7781):813-816. doi:10.1016/s0140-6736(72)92164-2
Weissmann, M. C., et al. "A trial of the ovulation method of family planning in Tonga." *Lancet (London, England)*, vol. 2, no. 7781, 1972, pp. 813-816.
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