Shrestha B, Homagai PL, Pokhrel MR, Ghimire KN. Exhausted Tea Leaves – a low cost bioadsorbent for the removal of Lead (II) and Zinc (II) ions from their aqueous solution. J. Nepal Chem. Soc. 2013;30:123-129. doi:10.3126/jncs.v30i0.9383