"This is the only known occasion in which the legality of actual combat use of the shotgun has been raised."
It is believed that this is the only known occasion on which such a medal has ever been awarded to an English lifeboat crew.
Loftus was present at the only known occasion of a ball bursting during a gaelic football match.
It was also, incidentally, the last known occasion that Massasoit and Squanto were in each other's company.
On the last known occasion of ShareReactor's forum being online, there were around 1,100,000 posts.
This is the last known occasion in which a full Supermarionation production was mounted.
At least on one known occasion the whole six thousand sat together to judge a single case (a plenary session of the Heliaia).
It is one of the few known occasions of a prominent physician speaking out against these practices.
This was the first known occasion when the name Mule Riders was used for the football team.
This is the first known occasion, in the world, on which local stamps were utilised to produce state stamps.