APG III (2009) An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III. Botanical Journal of the Linnean Society, 161: 105-121.
Cohen, K. M., Finney, S. C., Gibbard, P. L. and Fan, J.-X. (2013, updated) The ICS International Chronostratigraphic Chart. Episodes, 36: 199-204.
Ellis, B., Daly, D. C., Hickey, L. J., Johnson, K. R., Mitchell, J. D., Wilf, P. and Wing, S. L. (2009) Manual of Leaf Architecture. 190 pp. Cornell University Press, Ithaca, New York.
Hara, M. (2010) Climatic and historical factors controlling horizontal and vertical distribution patterns of two sympatric beech species, Fagus crenata Blume and Fagus japonica Maxim., in eastern Japan. Flora, 205: 161-170.
Hase, Y. (1988) Late Cenozoic history and paleoenvironment of southern Kyushu, Japan. Memoirs of the Faculty of Education, Kumamoto University. Natural Science, 23: 37-82. (in Japanese with English abstract)