Eugene Garfield, the "father of citation indexing of academic literature," who launched the Science Citation Index (SCI), which in turn led to the Web of Science, wrote: Citations are the formal, explicit linkages between papers that have particular points in common.
Eugene Garfield, "bapak pengindeksan sitiran literatur akademis," yang meluncurkan Science Citation Index (SCI), yang pada gilirannya mengarah pada Web of Science, wrote: Sitiran adalah hubungan formal dan eksplisit antara makalah yang memiliki titik-titik tertentu yang sama.