Received-SPF is a trace field specifically for recording an SPF evaluation. Authentication-Results is a broader framework that can record SPF, DKIM, DMARC and other authentication results.
Modern analysis commonly centers on trusted Authentication-Results fields because they can show several mechanisms together.
Trust boundary
Neither header should be trusted merely because it exists. An attacker can place fake fields in the message before sending it. Identify which headers were added by systems inside the receiving environment’s trusted boundary.