V.L. Rvachev, “On the analytical description of some geometric objects”, Reports of Ukrainian Academy of Sciences, vol. 153, no. 4, 1963, pp. 765–767 (in Russian) ↩
V. Shapiro, Semi-analytic geometry with R-Functions, Acta Numerica, Cambridge University Press, 2007, 16: 239-303 ↩
75 years to Vladimir L. Rvachev (75th anniversary biographical tribute) http://users.kpi.kharkov.ua/apm/all/rva75en.htm ↩