# Altshuller G.S., ‘To Find an Idea: Introduction to the Theory of Inventive Problems Solving’, (Novosibirsk, Nauka, 1986)# Altshuller G.S & Vertkin I., ‘Lines of Voidness Increase’, (Baku, 1987, Manuscript).
# Altshuller G.S., ‘To Find an Idea: Introduction to the Theory of Inventive Problems Solving’, (Novosibirsk, Nauka, 1986)# Altshuller G.S & Vertkin I., ‘Lines of Voidness Increase’, (Baku, 1987, Manuscript).