For an APA reference, you can treat the eNotes eText version A Doll's House as an e-book.
To cite an e-book in your Reference List, using APA, as usual, start with the author, last name first. In this instance, the author would be Henrik Ibsen.
Next, cite the year the e-book/eText was published. You can use the eNotes copyright year for that. Under the eText link, if you scroll down the navigation bar to the left, at the very bottom, you'll see the Copyright link. If you click on that, you'll see that the copyright year is 2008.
Next, we list the title of the e-book, in this case A Doll's House, plus, be sure to italicize it. Also, since APA is quirky, be sure to only capitalize the first word of the title.
Finally, we include Retrieved from and then the URL linking to the e-book. You can link to the actual act from the play that you referred to, since each act is on a different URL.
Last, but not least, include the original publishing year for the book. If you look at the "A Doll's House: Introduction" article listed under the eNotes "A Doll's House: Study Guide," we see that it was first published 1879.
The completed reference for the Reference List will mostly look like this, except that you will want to create a hanging indent, and formatting on this website does not allow for that:
- Ibsen, Henrik. (2008). A doll's house. Retrieved from http://www.enotes.com/dolls-house-text/act-i
If you also need help making your in-text citation, simply refer to the author, Ibsen, and the act you are referring to in your sentence and then use the eNotes' copyright year (2008). You will not need to refer to a page number at the end of your citation because, obviously, there isn't one.