Page URL:
https://www.etymonline.com/word/impregnable
HTML Link:
<a href="https://www.etymonline.com/word/impregnable">Etymology of impregnable by etymonline</a>
APA style:
Harper, D. (n.d.). Etymology of impregnable. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/impregnable
Chicago style:
Harper Douglas, “Etymology of impregnable,” Online Etymology Dictionary, accessed $(datetime), https://www.etymonline.com/word/impregnable.
MLA style:
Harper, Douglas. “Etymology of impregnable.” Online Etymology Dictionary, https://www.etymonline.com/word/impregnable. Accessed $(datetimeMla).
IEEE style:
D. Harper. “Etymology of impregnable.” Online Etymology Dictionary. https://www.etymonline.com/word/impregnable (accessed $(datetime)).