The Flash Season 2 Episode 14: Escape from Earth-2
Barry Allen from Earth 2 wears bow ties as a nod to the way Barry Allen was portrayed in the 50’s and 60’s. Barry rocked the bow tie in those days. Luckily, they did not include the green suits.
Arrow Season 4 Episode 14: Code of Silence
The Demolition Team was created by Len Wein and Dave Gibbons in Green Lantern #176 (May 1984). In the comics they were a construction crew inspired team of mercenaries who fought Green Lantern (Hal Jordan). They met their end at the hands of the OMACs (Observational Metahuman Activity Construct) in 2005.
Oliver telling Curtis that he is Terrific is a nod to Curtis Holt’s comic book namesake. In the comics Michael Holt is Mr. Terrific. Arrow named him Curtis instead of Michael. Many of Mr. Terrific’s gadgets have been seen on Arrow as prototypes.
DC’s Legends of Tomorrow Season 1 Episode 5: Fail-Safe
There was a nice nod to Wentworth Miller and Dominic Purcell’s previous TV Show together, Prison Break. The line was from Snart, “This is not my first Prison Break.” The sadistic Prison Guard is credited as being Mikhail Arkadin the same name as Pozhar, the Soviet Firestorm.