Management challenges in the 21st century. International conference. Management challenges in the 21st century : managing the unexpected: crisis and its impact on companies doing business in Slovakia : conference proceedings / zborník recenzovaných príspevkov : Bratislava, april 28, 2009. Trenčín : Vysoká škola manažmentu v Trenčíne, 2009. CD-ROM. VEGA 1/0016/09. ISBN 978-80-89306-05-3.