Siti Hannah Sabtu, Mohd Effendi @ Ewan Mohd Matore and Siti Mistima Maat 2024. Content Validity Of Teacher Teaching Quality Measurement Using The Six Sigma Approach Based On The Fuzzy Delphi Method. Educational Administration: Theory and Practice. 30, 5 (May 2024), 9788–9798. DOI:https://doi.org/10.53555/kuey.v30i5.4656.