Antakli, Saad, et al. “Simple Multi-Element Solid Phase Extraction Procedure to Determine Some Heavy Trace Metals in Honey by Flame Atomic Absorption Spectrometry”. Asian Journal of Chemistry, vol. 23, no. 7, Mar. 2011, pp. 3273-8, https://asianpubs.org/index.php/ajchem/article/view/10560.