Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:We compare KCDML not only with the state-of-art methods including our current work—CDML [38], Huang's method [43] and PCA combined with RBF (PCA-RBF) [43], but also with important baseline methods, such as PCA Kernel PCA (KPCA), LPP, Kernel LPP (KLPP) [44] and LDA.
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