If structure is what you are looking for MIL-STD-498 is good for that...
https://github.com/VCTLabs/MIL-STD-498/tree/master/MIL-STD-4...
https://github.com/VCTLabs/MIL-STD-498/tree/master/MIL-STD-4...
The lineage ends up at a lot of the IEEE / ISO standards in use today for more formal systems and software development.