Raúl González Muñoz and  Essam Shehab and  Martin Weinitzke and  Chris Fowler and  Paul Baguley,  Operational Software Maturity: An Aerospace Industry Analysis.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2017, vol. 129(9). 1001 - 1010
    [viewed 26 May 2020]. Available from: https://publications.waset.org/pdf/10007855.