Dear All I would like to use "Rarefaction" Does anyone have information about it and hoe I can calculate in the field of Plant Taxonomy and Flora. All the best sami ---------------------------------- With my Best Wishes Sami Hussein Rabei, Botany Department Faculty of Science at Damietta New Damietta, Damietta Egypt. +2017 3601618 (mobile) +2057 2403108 (home)