Adler, P., Schwarz, U., Syassen, K., Rozenberg, G. K., Machavariani, G. Y., Milner, A. P., et al. (1999). Collapse of the charge dispropertionation and covalency-driven insulator-metal transition in Sr3Fe2O7 under pressure. Physical Review B, 60(7), 4609-4617. doi:10.1103/PhysRevB.60.4609.