TY - JOUR T1 - Search engine coverage bias: evidence and possible causes JO - Information Processing & Management UR - http://dx.doi.org/10.1016/s0306-4573(03)00063-3 PY - 2004/07/01 AU - Vaughan L AU - Thelwall M ED - DO - DOI: 10.1016/s0306-4573(03)00063-3 PB - Elsevier BV VL - 40 IS - 4 SP - 693 EP - 707 Y2 - 2024/09/19 ER -