Jesli kogos interesuje - spis amerykanskich patentow:
formatting link
Poczatek listy:
U.S. Patent Documents
2341650 Feb., 1944 Quinlan.
2730474 Jan., 1956 Finholt et al.
2819850 Jan., 1958 Mathis.
3985310 Oct., 1976 Kent et al.
4140971 Feb., 1979 Blincoe.
4269366 May., 1981 Lindenmeyer.
4288041 Sep., 1981 Marzec et al.
4467972 Aug., 1984 Kaiser.
4548365 Oct., 1985 Marzec et al.
4771957 Sep., 1988 Schlake et al.
4779812 Oct., 1988 Fisher et al.
4812812 Mar., 1989 Flowerdew et al.
4821422 Apr., 1989 Porter.
4856721 Aug., 1989 Bonello et al.
4872618 Oct., 1989 Sato et al.
4884758 Dec., 1989 Hamkins.
4917316 Apr., 1990 Suzuki.
4917317 Apr., 1990 Iihama et al.
5143315 Sep., 1992 Faessel et al.
5165162 Nov., 1992 Charles.
5195682 Mar., 1993 Rabinovich.