Astala, Kari, Daniel Faraco, and László Székelyhidi Jr. 2009. “Convex Integration and the L^p Theory of Elliptic Equations”. ANNALI SCUOLA NORMALE SUPERIORE - CLASSE DI SCIENZE 7 (1):1-50. https://doi.org/10.2422/2036-2145.2008.1.01.