[Letter : 1843 June 10, Richard Wagner to Louis Spohr]
MLA
Wagner, Richard, 1813-1883, Weber, J. J., fl. 1862-1871. [Letter : 1843 June 10, Richard Wagner to Louis Spohr]. 1843 June 10. https://collections.library.yale.edu/catalog/16190982.
APA, 6th edition
Wagner, Richard, 1813-1883, & Weber, J. J., fl. 1862-1871. (1843 June 10)[[Letter : 1843 June 10, Richard Wagner to Louis Spohr]]. https://collections.library.yale.edu/catalog/16190982.