 The first published account of the ruins was made by <unk> Jacinto <unk> at the end of the 17th century . A number of visitors investigated the ruins of Toniná in the 19th century , the first being an expedition led by Guillaume <unk> in 1808 . John Lloyd Stephens and Frederick <unk> visited in 1840 , and Stephens wrote an extensive description of the site . Eduard <unk> and <unk> <unk> @-@ Sachs investigated the monuments at Toniná , publishing their reports at the turn of the 20th century . Karl Sapper visited the site in 1895 and 1896 . <unk> <unk> and Oliver La <unk> investigated the site in 1920s for Tulane University , publishing their reports in 1926 — 1927 . 
