mechanical linkage
...that Pafnuty Lvovich Chebyshev worked on mechanical linkage design for over thirty years which led to his work on Chebyshev polynomials?
...that <a class="mw-redirect" href="./Pafnuty_Lvovich_Chebyshev" id="mwA8s" rel="mw:WikiLink" title="Pafnuty Lvovich Chebyshev">Pafnuty Lvovich Chebyshev</a> worked on <b id="mwA8w"><a href="./Linkage_(mechanical)" id="mwA80" rel="mw:WikiLink" title="Linkage (mechanical)">mechanical linkage</a></b> design for over thirty years which led to his work on <a href="./Chebyshev_polynomials" id="mwA84" rel="mw:WikiLink" title="Chebyshev polynomials">Chebyshev polynomials</a>?