The toplevel building blocks may be documented with View or Component documents. From there you may drill deeper iterating with Blackbox and Whitebox views. You may also consider to connect the building blocks with the view documents that show the context of the system (see System Scope and Context).

Use the Transclude Documents Macro to transclude from these view documents according to the information needs of your stakeholders.

This is a free text section. You may have a separate Section for each dependency or relationship and list them here. The list may contain references using the Display Table Macro or you may transclude the relevant part for your audience with the Transclude Documents Macro.

If the dependencies and relationships to explain are only a few with a limited amount of text, you may simply employ the Section Macro and create some subsections.