Relations between Clar structures, Clar covers, and the sextet-rotation tree of a hexagonal system.

Shan Zhou Heping Zhang Ivan Gutman Relations between Clar structures, Clar covers, and the sextet-rotation tree of a hexagonal system. 1809-1821 2008 156 Discret. Appl. Math. 10 https://doi.org/10.1016/j.dam.2007.08.047 db/journals/dam/dam156.html#ZhouZG08