In my case, the 3D-reference link sent me to microsoft ad for Office 365. However, a simple browser search for "3D reference" did send me to a useful MS posting: Create a 3-D reference to the same cell range on multiple worksheets

The thread being 8 years old ( which makes me 72), no wonder links can point to new pages

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Using O365 v2503 - Did you know you can thank someone who helped you? Click on the tiny scale in the right upper hand corner of your helper's post

Oops. Found your comment, Pecoflyer, VERY HELPFUL. My thought was simply to suggest an alternative source since the original link apparently failed. Not to criticize. My Bad. (btw: I'm 77)