The <a href="https://en.wikipedia.org/wiki/National_Association_of_Professional_Base_Ball_Players" id="mwig" rel="mw:WikiLink" title="National Association of Professional Base Ball Players">National Association</a>, the first professional baseball league, opens its first season in <a href="https://en.wikipedia.org/wiki/Fort_Wayne,_Indiana" id="mwiw" rel="mw:WikiLink" title="Fort Wayne, Indiana">Fort Wayne, Indiana</a>.<sup about="#mwt94" class="mw-ref reference" data-mw='{"name":"ref","attrs":{},"body":{"id":"mw-reference-text-cite_note-15"}}' id="cite_ref-15" rel="dc:references" typeof="mw:Extension/ref"><a href="./May_4#cite_note-15" id="mwjA" style="counter-reset: mw-Ref 15;"><span class="mw-reflink-text" id="mwjQ">[15]</span></a></sup>
<span class="mw-reference-text" id="mw-reference-text-cite_note-15"><cite about="#mwt91" class="citation book cs1" id="CITEREFThorn2012">Thorn, John (2012). <a class="external text" href="https://books.google.com/books?id=gqF84JTKCNoC&amp;newbks=1&amp;newbks_redir=0&amp;printsec=frontcover#v=onepage&amp;q&amp;f=false" id="mwBig" rel="mw:ExtLink nofollow"><i id="mwBik">Baseball in the Garden of Eden: The Secret History of the Early Game</i></a>. New York: Simon &amp; Schuster. p.<span id="mwBio" typeof="mw:Entity"> </span>151. <a class="mw-redirect" href="./ISBN_(identifier)" id="mwBis" rel="mw:WikiLink" title="ISBN (identifier)">ISBN</a><span id="mwBiw" typeof="mw:Entity"> </span><a href="./Special:BookSources/9780743294041" id="mwBi0" rel="mw:WikiLink" title="Special:BookSources/9780743294041"><bdi id="mwBi4">9780743294041</bdi></a>.</cite><span about="#mwt91" class="Z3988" id="mwBi8" title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Baseball+in+the+Garden+of+Eden%3A+The+Secret+History+of+the+Early+Game&amp;rft.place=New+York&amp;rft.pages=151&amp;rft.pub=Simon+%26+Schuster&amp;rft.date=2012&amp;rft.isbn=9780743294041&amp;rft.aulast=Thorn&amp;rft.aufirst=John&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DgqF84JTKCNoC%26newbks%3D1%26newbks_redir%3D0%26printsec%3Dfrontcover%23v%3Donepage%26q%26f%3Dfalse&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AMay+4"></span></span>