The Plunger Principle

Do you guys know, if there is an inventor of the Plunger Principle? I read, that it's Jack McMillen, but I'm not sure.
Help, please!

---------- Post added at 06:41 PM ---------- Previous post was at 06:22 PM ----------

Plunger Principle

From MagicPedia, the free online encyclopedia for magicians by magicians.

History

There was some initial controversy over the invention of the original plunger principle used as a r***** c*** e*****.
A simple version of it first appeared in the September, 1931 issue no. 6 of Seven Circles Magazine by Lawrence Kam entitled Priceless Card R***. The trick was published again in 1935, claimed this time by Burling Hull, in his Stage Magic, No. 3 (pp. 79-82). William Larsen, Sr., in the first issue of Genii 1936 September defended Jack McMillen as the inventor, as showing Larsen and T. Page Wright the trick in 1928.

Just found it!^^
I hope, it's right...