1. 1. R. Bott, Notes on the Spencer resolution, Harvard University, Cambridge, Mass., 1963.
2. Existence of a homotopy operator for Spencer’s sequence in the analytic case;Buttin, C.;Pacific J. Math.,1967
3. 3. H. Cartan, Familles d’espaces complexes et fondements de la géométrie analytique, Séminaire Henri Cartan, 1961/62, Secrétariat Mathématique, Paris, 1963.
4. Vanishing theorem for an elliptic differential operator;Cenkl, Bohumil;J. Differential Geometry,1967
5. On Spencer’s estimate for 𝛿-Poincaré;Ehrenpreis, Leon;Ann. of Math. (2),1965