Diepreveen, Leonard.  Changing Voices: The Modern Quoting Poem.  Ann Arbor, MI: U of Michigan Press, 1993. 

        From the perspective of a scholar of twentieth-century American poetry, Diepreveen sees his project as an intervention in a discourse of "citationality" that he believes has come to stand in for any type of intertextuality, whether allusion, quotation, or formal citation.  Allusion and quotation are too different to be considered under the same concept, given how indirect an allusion may be and still qualify as an illusion.  Though he grants that the assumption of appropriated materials characterizes a great deal of formally innovative twentieth-century art, he restricts the scope of his study to poetry.  He aims, through practical criticism, to consider the impact that quotation has on features specific to poetry, such as stanzaic form, lineation, and metrics.  Unlike Gregory, Diepreveen argues that "quoting poems" are quintessentially American, "coming partly from preoccupations with antecedents (Eliot and Pound) and with authenticity (Moore, Cummings, Eliot, and Pound)." 

        Studying American modernist quoting poems illuminates other concepts crucial to modernism, like fragmentation, difficulty, and impersonality.   Diepreveen also looks at quotation as a destabilization of lyric voice that leads to the strands of postmodern art experimenting with ideas of dispersed subjectivity.  He argues, against Gregory, that quotations inevitably distort the subject of a poem, adducing the way that quotations continually redefine the subject of "The Octopus," Mt. Rainier.  He also reads Moore's famous statement about "Marriage" as an indicator that the poem falls under another genre, that of the anthology.  Anthologies pay for licenses, while Diepreveen claims that the modernists were content to steal, quoting Moore that a "good stealer is ipso facto a good inventor."  Does copyright law leave room for theft that will "make it [poetry] new," to quote Pound?  Is modernism criminal?  Are the supposed effects that quotations have on poems the traces of this criminality?