Many records regarding West African administration use this exact naming convention. If you are researching the administrative history of Yola, this would be a reference to a specific minute-sheet from a colonial office file.
If you need the specific contents of the "0217-06 Min" file, follow these steps: Yola Nakagawa 0217-06 Min
If this pertains to a land or business record in Yola, the state-level archives in Adamawa, Nigeria, would be the primary location for the physical documents. Many records regarding West African administration use this
Sites like JSTOR or Google Books often have snippets of these references in the "Sources and Bibliography" sections of historical theses. the state-level archives in Adamawa
06 typically points to the specific file or volume within that box.