Dimitar Georgiev and  Bogdan Bogdanov and  Yancho Hristov and  Irena Markovska,  The Removal of Cu (II) Ions from Aqueous Solutions on Synthetic Zeolite NaA.   journal   = {International Journal of Environmental and Ecological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2012, vol. 64(4). 214 - 218
    [viewed 29 November 2021]. Available from: https://publications.waset.org/pdf/3913.