A Convenient Synthetic Method for β-Alkoxy- and β-Phenoxyacrylic Acids and 3,4-Dihydro-2H-pyran-5- and 2,3-Dihydrofuran-4-carboxylic Acids - Hojo, Masaru; Masuda, Ryōichi; Sakaguchi, Syūhei; Takagawa, Makoto (Synthesis, 1986)