Sitnikova, E. G. A strong zero theorem for an elliptic equation of higher order. (English) Zbl 0216.37804 Math. USSR, Sb. 10(1970), 349-367 (1971). Cited in 1 ReviewCited in 1 Document MSC: 35J30 Higher-order elliptic equations 35B05 Oscillation, zeros of solutions, mean value theorems, etc. in context of PDEs PDF BibTeX XML Cite \textit{E. G. Sitnikova}, Math. USSR, Sb. 10, 349--367 (1971; Zbl 0216.37804) Full Text: DOI OpenURL