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Zordan, T.A.; Hurkot, D.G.; Peterson, M.; Hepler, L.G., Enthalpies and entropies of melting from differential scanning calorimetry and freezing point depressions: urea, methylurea, 1, 1-dimethylurea, 1, 3- dimethylurea, tetramethylurea, and thiourea, Thermochim. Acta, 1972, 5, 21. [all data]