Patents.
3,310,701; 3,311,747; 3,311,775; 3,311,777; 3,312,518; 3,317,268; 3,317,727; 3,317,739; 3,319,115; 3,319,119; 3,320,061; 3,320,417; 3,322,034; 3,324,760; 3,325,240; 3,325,299; 3,325,825; 3,327,150; 3,331,299; 3,333,101; 3,334,217; 3,335,311; 3,337,729; 3,337,734; 3,337,738; 3,340,108; 3,341,274; 3,343,023; 3,343,026; 3,343,449; 3,343,451; 3,343,957; 3,344,281; 3,345,174; 3,345,176; 3,345,905; 3,347,132; 3,347,615; 3,348,900; 3,348,901; 3,350,155; 3,350,157; 3,351,412; 3,351,755; 3,351,756; 3,353,891; 3,353,892; 3,353,895; 3,355,234; 3,355,308; 3,355,313; 3,355,579; 3,355,588; 3,355,981; 3,355,979; 3,356,002; 3,357,268; 3,357,776; 3,356,848; 3,357,774; 3,358,149; 3,359,057; 3,359,850; 3,360,328; 3,360,659; 3,361,512; 3,362,770; 3,363,962;