1911, Initials of Thomas Levick, carved in lava, Isla Santa Cruz.

 19??, Initials of Thomas Levick, carved in rock, Floreana highlands.

1920, in Ralph Stock's Cruise of the Dream Ship.

1923, in William Beebe's Galápagos: World's End.

1925, in Stein Hoff's Drømmen om Galapagos.

1936, in Rolf Blomberg's Underliga Mäniskor och Underliga Djur.