., S., E. W. LFX, E. Rohaeti, A. R. P. Sari, and R. D. Astuti. “Exploring Item Validity: Critical-Science Process Skills Integrated Assessment Instrument on Electrolyte Solution and Acid Base Matter”. The International Journal of Science & Technoledge, vol. 5, no. 1, Jan. 2017, https://internationaljournalcorner.com/index.php/theijst/article/view/123355.