Guzmán, Fanny, Sonia Barberis, and Andrés Illanes. 2007. “Peptide Synthesis: Chemical or Enzymatic”. Electronic Journal of Biotechnology 10 (2). Valparaíso, Chile:0-0. https://preprints.pucv.cl/index.php/ejbiotechnology/article/view/v10n2-13.