Salamaga, M. and Sala, K. (2015) “Study on the Effectiveness of Investments in Gold Using a Method TRB”, Krakow Review of Economics and Management/Zeszyty Naukowe Uniwersytetu Ekonomicznego w Krakowie, (6(930), pp. 73–86. doi:10.15678/ZNUEK.2014.0930.0605.