[[1] Glass A., Polskie Konstrukcje Lotnicze 1893–1939, Wydawnictwa Komunikacji i Łączności, 1976.]Search in Google Scholar
[[2] Malak E., Prototypy samolotów bojowych Polska 1936–1939, Wydawnictwo Uniwersytetu Wrocławskiego, 1990.]Search in Google Scholar
[[3] Malak E., Prototypy samolotów bojowych i zakłady lotnicze Polska 1930–1939, Instytut Wydawniczy ERICA, 2011.]Search in Google Scholar
[[4] Malak E., DZIEŁO GENERAŁA RAYSKIEGO Technika i zarządzanie, Instytut Historii Nauki PAN, 2015.]Search in Google Scholar
[[5] Cynk J., Polish Aircraft 1893–1939, Putnam & Company, 1971.]Search in Google Scholar
[[6] https://max3d.pl/forums/topic/100461-pzl-p-50-a-jastrząb/, (member: kliment woroszyłow).]Search in Google Scholar
[[7] Mazur W., Projekty i prototypy samolotów myśliwskich, Cykl: Wielki Leksykon Uzbrojenia Wrzesień 1939, Nr 73, Wydawnictwo Edipresse, 2015.]Search in Google Scholar
[[8] Agencja Lotnicza Altair, www.altair.com.pl]Search in Google Scholar
[[9] Bodnar M., Crowdsourced Damage Mapping for Disaster Emergency Response — the 2015 Nepal Earthquake Case Study, United Nations/India Workshop on the Use of Earth Observation Data in Disaster Management and Risk Reduction: Sharing the Asian Experience, 2016.]Search in Google Scholar
[[10] Yang Hui J., Crowdsourcing for National Security, Policy Report, Centre of Excellence for National Security (CENS), S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University (NTU), 2015.]Search in Google Scholar
[[11] Brabham D. C., Crowdsourcing, The MIT Press Essential Knowledge Series, 2013.10.7551/mitpress/9693.001.0001]Search in Google Scholar
[[12] Green A., de Hoyos M., Barnes S-A., Baldauf B., Behle H., CrowdEmploy Crowdsourcing Case Studies: An Empirical Investigation into the Impact of Crowdsourcing on Employability, European Commission, Joint Research Centre, Institute for Prospective Technological Studies, JRC Technical Reports, 2013.]Search in Google Scholar
[[13] WeTheCrowd, www.wetehcrowd.pl]Search in Google Scholar
[[14] Kowalska M., Crowdsourcing internetowy — Pozytywny wymiar partycypacji społecznej, Wydawnictwo SBP, 2016.]Search in Google Scholar
[[15] Łukasiewicz Research Network — Institute of Aviation, www.ilot.edu.pl]Search in Google Scholar
[[16] Scienceship, www.scienceship.com]Search in Google Scholar
[[17] Muzeum Lotnictwa Polskiego, www.muzeumlotnictwa.pl]Search in Google Scholar
[[18] Szafran K., Michalczyk M. (2018) Various types of the rotorcraft design in the context of aerospace regulations'. Transaction of the Institute of Aviation. ISSN 0509-6669 Nr 1 (250). pp. 142–149.10.2478/tar-2018-0010]Search in Google Scholar
[[19] Szafran K. (2017) TRAINEESHIPS INDUSTRIAL AND PROFESSIONAL PRACTICE AS EFFECTIVE MECHANISM OF MARKETING OF THE SCIENTIFIC AND RESEARCH INSTITUTE. DOI: 10.14611/minib.23.03.2017.02 MINIB, Vol. 23, Issue 1, p. 21–36.]Search in Google Scholar
[[20] Szafran K., Kramarski I., (2018) Fatigue Degradation of the Structure of Parachute Systems. Fatigue of Aircraft Structures. The Journal of Institute of Aviation. ISSN 2081-7738, eISSN 2300-7591, Vol. 2018 pp. 93–103.10.2478/fas-2018-0009]Search in Google Scholar