this upload of yours has not yet been officially added to IMSLP. You need to:
1) Go to the page for Tansman
2) Click the link there to Add a piece to this composer page
2a) Give the piece a title such as "Sonata for two pianos" and fill in any other info you know, such as the opus number (the name of the composer will be supplied automatically)
3) Once you've done that, go to the page for "Sonata for two pianos (Tansman, Alexandre)" and click on the link to Add a file to this page
4) On the next page, select the link where it says Use this form for files already uploaded
5) On that page, the filename you uploaded was Tansman - Sonata for two pianos.pdf. Please fill in the other info and click Submit!.