The last works of Keith Weber and his group are concerned with mathematicians proving. For instance, Weber and Ramos (2011) is about how mathematicians read proofs.
Inglis and Alcock (2012, Journal of Research in Mathematics Education) investigate experts' and students' reading of mathematical proofs.
More distant, Koeneman, Goedhart and Ossevoort (2014, Educational Studies in Mathematics) investigate science students' reading of scientific (but non-mathematical) papers
You can find papers from Jose Otero Gutierrez, Universidad de Alcala (Spain). In my group, we did something with statements Physics Problem Solving. One of my PhD students worked with Sitational Model in her doctoral thesis. She is Maria Elena Truyol