Model independent bounds on the modulus of the pion form factor on the unitarity cut below the ωπ thresholdB. Ananthanarayan, I. Caprini, Diganta Das and I.Sentitemsu ImsongEur. Phys. J. C, 72 10 (2012) 2192DOI: https://doi.org/10.1140/epjc/s10052-012-2192-x