Inventor: Heemskerk, Harold
Inventor: Bruinen, Edward
Inventor: Bruinen, Edward
Inventor: Spruit, Adrianus Theodorus
Inventor: Strangman, Elizabeth, Gough, Graham
Inventor: Hollingsworth, Donald
Inventor: Rudolph, Nathan H.
Inventor: Carl George Klehm
Inventor: Carl George Klehm
Inventor: Carl George Klehm