-In the second section we describe our approach of detailed document comparison.
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-We also discuss the performance ...
+In the first section we will introduce methods, which took part in
+PAN 2012 competition\footnote{\url{http://pan.webis.de/}} in plagiarism detection, for candidate document retrieval from online sources.
+The task was to retrieve a set of candidate source documents that may had served as an original for plagiarism.
+During the competition, there were several measures of performance such as: i) Number of queries submitted,
+ii) Number of web pages downloaded, iii) Precision and recall of web pages downloaded regarding the actual sources,
+iv) Number of queries until the first actual source is found, v) Number of downloads until the first actual source is downloaded.
+Nevertheless, the overall performance measure was not set, thus we mainly focus on minimizing the query workload.
+%In the PAN 2012 candidate document retrieval test corpus, there were 32 text documents all contained at least one plagiarism case.
+%The documents were approximately 30 KB of size, the smallest were 18 KB and the largest were 44 KB.