Schuh, C., Raudabaugh, J. L., Kromoser, R., Strohmer, M. F., Triplat, A., & Pearce, J. (2020). The Purchasing Chessboard. 3rd ed. 2017. Springer New York.

Schuh, Christian, Joseph L. Raudabaugh, Robert Kromoser, Michael F. Strohmer, Alenka Triplat, ja James Pearce. The Purchasing Chessboard. 3rd Ed. 2017. Springer New York, 2020.

Schuh, Christian, et al. The Purchasing Chessboard. 3rd Ed. 2017. Springer New York, 2020.