The classical approach organizes this structure via operads, while the recent approach of Jacob Lurie deals with it using -operads in -categories.
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One can define an infinity-category of spectra (as done by Lurie).
ZX Spectrum | spectrum | Der Ring des Nibelungen | Ring of Honor | The Fellowship of the Ring | Spectrum | The Ring (magazine) | Ring of Fire | The Ring | Ring | The Lord of the Rings: The Fellowship of the Ring | ''The Ring'' | Bull Ring, Birmingham | The Promise Ring | Ring 2 | electromagnetic spectrum | Twin Ring Motegi | Ring Round the Moon | E-Ring | Bull Ring | The Seven Habits of Highly Effective People | Sheffield Inner Ring Road | Scarff ring | Ring of Fire (song) | Ring Lardner | One Ring | Ku-ring-gai Council | World Series ring | Visible spectrum | Tub Ring |