For Hydrophyllaceae
Constance, L. 1963. Chromosome number and classification in Hydrophyllaceae. Brittonia 15: 273-285.
Ferguson, D.M. 1998. Phylogenetic analysis and relationships in Hydrophyllaceae based on ndhF sequence data. Systematic Botany 23: 253-268.
Hofmann et al. In Kadereit, J.W., and V. Bittrich. 2016. The families and genera of flowering plants. XIV. Flowering plants – Eudicots – Aquifoliales, Boraginales, Bruniales, Dipsacales, Escalloniales, Garryales, Paracryphiales, Solanales (except Convolvulaceae), Icacinaceae, Metteniusaceae, Vahliaceae. Springer, Berlin. 412 pp.