How can I find musicologists' analysis of individual Modernist pieces online?

Question

How can I find musicologists' analyses that focuses on a single piece? I know they're probably pay-walled. Google Scholar yields nothing for Xenakis's Metastasis (1957).

To wit, I'm seeking articles for Xenakis's compositions like

• Alegant, Brian. “A Model for the Pitch Structure of Webern's Op. 23 No. 1, ‘Das Dunkle Herz.’” Music Theory Spectrum, vol. 13, no. 2, 1991, pp. 127–146. JSTOR, www.jstor.org/stable/745895.

• Alegant, Brian. “Unveiling Schoenberg's Op. 33b.” Music Theory Spectrum, vol. 18, no. 2, 1996, pp. 143–166. JSTOR, www.jstor.org/stable/746022.

• Ilias Chrissochoidis, C Mitsakis, S Houliaras. Set theory in Xenakis' EONTA.

Answer 1

Allowing you're still looking for an answer...

There's an article on Metastasis specifically, in French, on JSTOR:

Anne-Sylvie Barthel-Calvet. "MÉTASTASSIS-Analyse: Un Texte Inédit De Iannis Xenakis Sur Metastasis." Revue De Musicologie 89, no. 1 (2003): 129-87. Accessed July 11, 2020. www.jstor.org/stable/4494838.

JSTOR is a good place to search. The journal Perspectives of New Music might be of particular interest as the kind of analyses you're looking for are a primary focus. There are many articles on Xenakis as well as other composers and compositions.

When I'm looking for analyses, most often I search through the bibliographies of articles mentioning the composer or piece.