1. Alter S (2013) Work system theory: overview of core concepts, extensions, and challenges for the future. J Assoc Inf Syst 14(2):72–121
2. Brynjolfsson E, McAfee A (2014) The second machine age: work, progress, and prosperity in a time of brilliant technologies. WW Norton & Company, New York
3. Hammon D-KL, Hippner H (2012) Crowdsourcing. Bus Inf Syst Eng 4(3):163–166
4. Kuek SC, Paradi-Guilford C, Fayomi T, Imaizumi S, Ipeirotis P, Pina P, Singh M (2015) The global opportunity in online outsourcing. World Bank Group, Washington
5. Leimeister JM (2012) Crowdsourcing. Control Manag 56(6):388–392