Sabelli, R. and Griffis, L. 2021. Technical Note: Internal Second-Order Stiffness: A Refined Approach to the Rm Coefficient to Account for the Influence of P-? on P-?. Engineering Journal. 58, 2 (Jun. 2021), 139–146. DOI:https://doi.org/10.62913/engj.v58i2.1173.