By years: papers in scientific journals and proceedings
Years	Number		Years	Number		Years	Number		Years	Number		Years	Number		Years	Number		Years	Number		Years	Number
			1930	6		1940	2		1950	5		1960	5		1970	2		1980	1		1990	1
			1931	0		1941	2		1951	10		1961	5		1971	4		1981	4		1991	0
			1932	7		1942	2		1952	2		1962	2		1972	2		1982	4		1992	0
			1933	5		1943	2		1953	6		1963	2		1973	3		1983	2		1993	0
			1934	2		1944	6		1954	9		1964	4		1974	5		1984	3		1994	0
			1935	3		1945	4		1955	5		1965	3		1975	4		1985	6		1995	0
1926	2		1936	5		1946	2		1956	4		1966	1		1976	2		1986	1		1996	0
1927	5		1937	2		1947	2		1957	14		1967	0		1977	2		1987	1		1997	1
1928	3		1938	6		1948	2		1958	8		1968	3		1978	2		1988	1		1998	1
1929	6		1939	4		1949	5		1959	1		1969	2		1979	3		1989	2		1999	1