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Aclander, J., Altman, A., Ashery, D., Feltham, A., Hahn, H., Hutcheon, D., Jones, G., MayTal-Beck, S., Moinester, M. A., Niskanen, J. A., Ottewell, D., Pavan, M., Rahav, A., Sevior, M., & Smith, G. R. (1992). Proton polarization from pi + absorption in 3He. Physical review letters, 68(20), 3012-3015. https://doi.org/10.1103/PhysRevLett.68.3012

Aclander, et al. "Proton polarization from pi + absorption in 3He." Physical review letters vol. 68,20 (1992): 3012-3015. doi: https://doi.org/10.1103/PhysRevLett.68.3012