
If you were to TRAVEL back in time
and knock me unconscious...
The Big Bang Theory Season 1, Episode 14

Which is a TRAVEL book
within the actual book.
The Big Bang Theory Season 8, Episode 8

SHELDON: You know, I've been thinking
about time TRAVEL again.
The Big Bang Theory Season 1, Episode 4

Oh, and I just found a new TRAVEL cup
for Sheldon.
The Big Bang Theory Season 9, Episode 16

the TRAVEL time from Mordor to the Shire.
The Big Bang Theory Season 9, Episode 8