MLA multiple parenthetical citation essay without page numbers

Question

I have an older source that has no pagination. My question concerns the correct mode of multiple parenthetical in-text reference to the source according to MLA style.

In the works cited section:

Smith, Alexander. "The Problems of Writing." New Inquiry (1940): n. pag.

In text (version 1):

Smith argues that writing is "a problem of its own" (1940). He goes on to refer to the "complicated process of writing a text." He explains it in ...

Question: How do I back up the second, third, etc. reference to the unpaginated source in my own text? Is the text above right or do I need to have the year in brackets every time I quote from the text? Something like:

version 2: Smith argues that writing is "a problem of its own" (1940). He goes on to refer to the "complicated process of writing a text" (1940). He explains...

Or do I reference "n.pag." in the text:

version 3: Smith argues that writing is "a problem of its own" (1940 n. pag.). He goes on to refer to the "complicated process of writing a text" (n. pag.). He explains...

Thank you very much!

Answer 1

According to the University of Maryland, University College's page on MLA style:

"If you are citing an entire work, or a work that has no page numbers, you want to include information that will allow the reader to locate the source in your works cited list. If it is not possible to include this information in the text, follow the sentence where the citation needs to be made with an in-text citation containing only the name of the author."

They offer the following examples:

In his article "Allston Gothic," local historian Forman Jackson demonstrates how completely the neighborhood's gruesome past has been forgotten by its residents.

OR

A recent newspaper article demonstrated just how thoroughly the neighborhood's gruesome past has been forgotten by its residents (Jackson).

source: http://www.umuc.edu/library/libhow/mla_examples.cfm#intext