May 您好：

依據AACR 2規則的1.1F1，在著錄職責敘述時，依照他們在主要著錄來源上的呈現形式照錄，如果是非得自主要著錄來源者，才需要加方括號。以下為規則原文：

Transcribe statements of responsibility appearing prominently in the item in the form in which they appear there. If a statement of responsibility is taken from a source other than the chief source of information, enclose it in square brackets.

而依據1.1F5，當出現在主要著錄來源上的同一種職責敘述中列出了超過3個個人或團體名稱時，才需要以「 … [et al.]」做簡省的著錄，規則原文如下：

If a single statement of responsibility names more than three persons or corporate bodies performing the same function, or with the same degree of responsibility, omit all but the first of each group of such persons or bodies. Indicate the omission by the mark of omission ( … ) and add et al. (or its equivalent in a nonroman script) in square brackets.

您所提的例子中，在書名頁有「contributors, Semih Olcmen, Marcus Ashford, et al.」的職責敘述，由於書名頁為主要著錄來源，且職責敘述中僅列出2位個人名稱，因此在欄位245分欄$c可依書名頁上的職責敘述照錄為：

245    …….. /  $c contributors, Semih Olcmen, Marcus Ashford, et al.

以上資訊供您參考。

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