DRAŠKOVIĆ, Veselin; et al. Knowledge - keystone of the modern economy. 1st ed.. Celje [etc.] : SPH - Scientific Publishing Hub, 2013. VIII, 272 str.. http://sphub.org/wp-content/uploads/2013/11/Complete-PDF-version-KNOWLEDGE-KEYSTONE-OF-THE-MODERN-ECONOMY1.pdf. ISBN 978-961-6948-00-5.