Huang, Y.-X., Schäfer, G., Carrillo-Cabrera, W., Cardoso, R., Schnelle, W., Zhao, J.-T., et al. (2001). Open-Framework Borophosphates: (NH4)0.4FeII0.55FeIII0.5(H2O)2[BP2O8] ·0.6H2O and NH4FeIII[BP2O8(OH)]. Chemistry of Materials, 13, 4348-4354. doi:10.1021/cm011101e.