Wulbert, D. E. Averaging projections. (English) Zbl 0179.18201 Ill. J. Math. 13, 689-693 (1969). Page: −5 −4 −3 −2 −1 ±0 +1 +2 +3 +4 +5 Show Scanned Page Cited in 6 Documents Keywords:functional analysis PDF BibTeX XML Cite \textit{D. E. Wulbert}, Ill. J. Math. 13, 689--693 (1969; Zbl 0179.18201) OpenURL