Caxton 1483,第11頁. Caxton, William. Bradley, Henry , 编. Dialogues in French and English. Kegan Paul, Trench, Trubner & Co. Ltd. for the Early English Text Society. 1890: 11 [c. 1483] [11 January 2014].
Fries 1969,第215頁. Fries, Joseph P. The inflections and syntax of present-day American English with especial reference to social differences or class dialects: the report of an investigation financed by the National Council of Teachers of English and supported by the Modern Language Association and the Linguistic Society of America. Bolton, W.F.; Crystal (编). The English Language Volume 2 Essays by Linguistics and Men of Letters 1858-1964. Cambridge University Press Archive. 1969 [1940] [2014-07-26]. ISBN 9780451140760. (原始内容存档于2015-04-02).
Warenda 1993,第101頁. Warenda, Amy. They(pdf). The WAC Journal. April 1993, 4 [28 December 2013]. (原始内容存档(PDF)于2020-12-06).
Fries 1969,第215頁. Fries, Joseph P. The inflections and syntax of present-day American English with especial reference to social differences or class dialects: the report of an investigation financed by the National Council of Teachers of English and supported by the Modern Language Association and the Linguistic Society of America. Bolton, W.F.; Crystal (编). The English Language Volume 2 Essays by Linguistics and Men of Letters 1858-1964. Cambridge University Press Archive. 1969 [1940] [2014-07-26]. ISBN 9780451140760. (原始内容存档于2015-04-02).
Newman 1998. Newman, Michael. What Can Pronouns Tell Us? A Case Study of English Epicenes. Studies in language (John Benjamins). 1998, 22 (2): 353–389. ISSN 0378-4177.