Grädel, E., & Kreutzer, S. (1999). Descriptive Complexity Theory for Constraint Databases. Springer.
芝加哥风格引文Grädel, E., 与 S. Kreutzer. Descriptive Complexity Theory for Constraint Databases. Springer, 1999.
MLA引文Grädel, E., 与 S. Kreutzer. Descriptive Complexity Theory for Constraint Databases. Springer, 1999.
警告：这些引文格式不一定是100％准确.