Wenclawiak, Bernd W.; Koch, Michael; Hadjicostas, Evsevios (2010-08-05). Quality Assurance in Analytical Chemistry: Training and Teaching. Springer Science & Business Media. p. 229. ISBN 978-3-642-13609-2. 978-3-642-13609-2 ↩
Reichenbächer, Manfred; Einax, Jürgen W. (2011-02-16). Challenges in Analytical Quality Assurance. Springer Science & Business Media. p. 108. ISBN 978-3-642-16595-5. 978-3-642-16595-5 ↩