I am writing a secondary textbook to be used in public schools. In my state, the textbooks must adhere to standards, such as the Common Core State Standards (CCSS). It is typical for a textbook to contain an index for teachers to check where in the textbook which standards are used. I've used the following code to create such an index, if I simply place `\learned{}` somewhere containing the standard's ID, it creates a custom index entry, and `\placelearned` displays that index. \defineregister[learned][compress=yes] \setupregister[learned][style=sansbold, textstyle=slanted, n=1, pagenumber=yes] \starttext \learned{CCSS+W.7.3} \input knuth \learned{CCSS+W.7.3} \input knuth \learned{CCSS+W.7.1} \startchapter[title=Standards] \placelearned \stopchapter \stoptext This prints an index like this: Standards c CSS W.7.1 1 W.7.3 1 My problem is my textbook also includes four separate workbooks. I need the index to show my publisher that I've covered all 300+ standards, so I need the index at the back of the textbook to also contain details of which pages in each workbook the standards are found. How can I combine the index so it refers to all books? Something like this: Standards c CSS W.7.1 T 1, Wk.1 3-8, 12, Wk.2 8-9, 60-61 W.7.3 T 1, Wk.1 3-8, 12, Wk.2 8-9, 60-61, Wk.3 1-2, 54, 70, 90, Wk.4 99, 102, 104 ...or possibly like this... Standards c CSS W.7.1 Textbook: 1 Workbook 1: 3-8, 12 Workbook 2: 8-9, 60-61 W.7.3 Textbook: 1 Workbook 1: 3-8, 12 Workbook 2: 8-9, 60-61 Workbook 3: 1-2, 54, 70, 90 Workbook 4: 99, 102, 104 Is there any way to print an index that covers pages across multiple books? --Joel