1. e-Governance, M.O.: Integrated information system of the state administration ADMINISTRATIVE REGISTER (2019). https://www.government.bg/, https://iisda.government.bg/
2. Fitzgerald, M.K.: Embracing digital technology: a new strategic imperative. MIT Sloan Manag. Rev. (2013)
3. Kane, G.P.: The Technology Fallacy: How People are the Real Key to Digital Transformation. MIT Press, Massachusetts (2019)
4. Westerman, G.B.: Leading Digital: Turning Technology into Business Transformation. Harvard Business Press, Boston (2014)
5. Larsson, A.T.: Digital Transformation and Public Services. Taylor & Francis Routledge, New York (2019)