Onherstelbaar verbeterd ("irreparably improved") is a slim volume of poetry by Dutch poet Gerrit Komrij.
Published in 1981 by Amsterdam publisher C. J. Aarts, it contained five pastiches[1] of canonical Dutch (expressionist[2]) sonnets, and five original sonnets.
The five pastiches are of poems by Gerrit Achterberg, J. C. Bloem, Willem Kloos, Hendrik Marsman, and Martinus Nijhoff.
[3] The third edition, published in 1994, added another pastiche of a J. C. Bloem poem, "De Dapperstraat", now remade as "De Kalverstraat".
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