https://www.saccharometabolism.com/2016/06/30/cnbr-activated-sepharose-beads-30-ml-that-contains-nine-mg-of-covalently-attached-energetic-phosphorylated-without-or-with-one-mm-atp-or-inactive-erk2-were-incubated-with-three-mg-of-indicated-pur/