Pengarang: Matthias Baaz and George Metcalfe
| No. Panggil: Journal of Logic and Computation February 2010, 20 (1), p. 35-54
| Penerbitan: Oxford University Press
Pengarang: Manuel Bodirsky, Peter Jonsson, and Timo von Oertzen
| No. Panggil: Journal of Logic and Computation June 2012, 22 (3), p. 643-660
| Penerbitan: Oxford University Press
Pengarang: Guang Lan Zhang, Angelika B. Riemer, Derin B. Keskin, Lou Chitkushev, dll
| No. Panggil: Database (Volume 2014, p.bau031)
| Penerbitan: Oxford University Press