Here's a link to the general documentation for NWce7.1:
SAP NetWeaver Composition Environment 7.1 – SAP Help Portal Page
And here's a link to the security-specific integration steps that should explain exactly what you need for SSO:
Configuring Authentication and Single Sign-On - SAP Library
That will enable you to reach those various back end systems with users who've authenticated to your Portal. I'm assuming that's what you meant by "integrations". If you also need info for creating and consuming content from these systems in that portal... that's a whole different story and a lot more research you'll need to do. It's not realistic for anyone here to list every step you might need in those scenarios and that's something that the Portal and Basis folks on your project would take care of anyway.
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