The Professor Elm's Lecture (213 / 214) card can be found in the Lost Thunder set.
Recently sold 4 times and based on those sales is worth around £40.89.
Currently, there are 6 open listings for this card on ebay.
This card sells in the range of £39.16 to £42.62, making it very stable.
This Rare Ultra card was illustrated by Hideki Ishikawa.