# Writing a N-to-1 Element or Muxer
N-to-1 elements have been previously mentioned and discussed in both
-[Request and Sometimes pads](pwg-advanced-request.md) and in
-[Different scheduling modes](pwg-scheduling.md). The main noteworthy
+[Request and Sometimes pads](pwg/advanced/request.md) and in
+[Different scheduling modes](pwg/advanced/scheduling.md). The main noteworthy
thing about N-to-1 elements is that each pad is push-based in its own
thread, and the N-to-1 element synchronizes those streams by
expected-timestamp-based logic. This means it lets all streams wait
If you need anything more difficult, such as "don't-grab-a-new-buffer
until a given timestamp" or something like that, you'll need to do this
yourself.
-