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:Most early work assumed some limited amount of supervision (e.g., a small list of translation seeds) for this task, recent work has shown that unsupervised methods can perform on-par and often above early supervised methods [Artetxe et al., 2018a, Conneau et al., 2018].
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