Cheeger, J. (1 August 1999). "Differentiability of Lipschitz functions on metric measure spaces". Geometric and Functional Analysis. 9 (3): 428–517. doi:10.1007/s000390050094. S2CID120149485.
Cheeger, J. (1 August 1999). "Differentiability of Lipschitz functions on metric measure spaces". Geometric and Functional Analysis. 9 (3): 428–517. doi:10.1007/s000390050094. S2CID120149485.