An architecture becomes reference if it's generic enough, available and used by many in the community.
The level of abstraction of an architecture should be high enough to serve its scope--for instance, a business domain or an industry. But the architectures at these various abstraction levels should be part of an architecture continuum, as TOGAF states.
Reference architectures can be created for many business and technology functions.
A reference model can be customised to create an architecture for your domain or enterprise. By comparison, the generic plan of a car can be used to describe your own car by specifying the generic parts: body is sedan, engine is diesel, transmission is automatic...
I recently proposed a single-page generic business architecture here that can be used as a reference. It is an extension to Porter's value chain concept from which support activities extract the governance (coordinates all other) and the development function. The reasons are becoming more clear today. Many companies, like Apple, do not manufacture their products in-house any longer, but solely develop, or design, them there. Development becomes, in many cases, the core activity today, parting with a past when product delivery was core.
Also, governance is the only function that forms and identifies an enterprise when all development, manufacturing, sales, services and support functions have been outsourced. This is the new Intelligent enterprise the outsourcing trend pushes us to, where the entrepreneurial team plans and coordinates all activities in the value system, professionally performed by specialized firms. But even if a company does not develop, manufacture and sell the products any longer, it (the governance function) still has to orchestrate the overall activity, deliveries, sales and financials.
The singl- page GODS generic model consists of functions and flows (capabilities and value streams) in interconnection.
How could this generic business architecture model be used as reference?
- Select the key business functions (and add/remove them) that represent your enterprise.
- Customize business flows (market, plan, produce, deliver, sale, service, borrow, recruit, manage IT ...).
- Proceed with the next level of decomposition, in iterations, to describe for both functions and flows. For that, you may get inspiration from one of the process frameworks in existence (APQC, VRM, eTOM...), since they aim to list most key process in an enterprise.
- Then you may want to continue to develop the EA at this stage
The book "An Enterprise Architecture Development Framework", now available as an Amazon Kindle e-book, describes reference business, information and IT architectures (i.e., templates) and organization reference designs. A novel EA frameworks binds them all to enable navigation for impact analysis, business process improvement.