The seven basic tools of quality. London: Improvement and Innovation.com (30 қараша 2007). — «Ishikawa had a desire to ‘democratise quality’: that is to say, he wanted to make quality control comprehensible to all workers, and inspired by Deming’s lectures, he formalised the Seven Basic Tools of Quality Control.» Тексерілді, 18 мамыр 2013.