Example in answer to the question Click How to create a document with unequal page sizes? | iText 5 PDF Development Guide
unequalpages
##GITHUB:https://github.com/itext/i5js-sandbox/blob/master/src/main/java/sandbox/objects/UnequalPages.java##
changemargin
##GITHUB:https://github.com/itext/i5js-sandbox/blob/master/src/main/java/sandbox/objects/ChangeMargin.java##
Results
https://github.com/itext/i5js-sandbox/blob/master/cmpfiles/objects/cmp_unequal_pages.pdf
https://github.com/itext/i5js-sandbox/blob/master/cmpfiles/objects/cmp_change_margin.pdf