His name is actually spelt "Pedersen." IMHO, his most clever design was the Pedersen device, which was like a mini-submachine gun adapter for the Springfield rifle, and would give the average infantryman a high volume of fire for short range engagements in the trenches of WWI.
I had a French model 1935 which used a cartridge identical to the one used in the Pedersen device.
It was beautifully machined and had a locked breech similar to the 1911. I wish I still had it.