Gottwald, J., Demco, D. E., Graf, R., & Spiess, H. W. (1995). HIGH-RESOLUTION DOUBLE-QUANTUM NMR-SPECTROSCOPY OF HOMONUCLEAR SPIN PAIRS AND PROTON CONNECTIVITIES IN SOLIDS. Chemical Physics Letters, 243(3-4), 314-323. doi:10.1016/0009-2614(95)00872-2.