Improved optical limiting of triazine-linked mono-, bis- and tris-phthalocyaninesQuan Miao, Zhaoyang Sang, Rengang Song, Min Liang, Erping Sun and Yan XuEur. Phys. J. D, 73 2 (2019) 35DOI: https://doi.org/10.1140/epjd/e2019-90577-2