Paper: "Sampling design and model selection influence on predictions of chemical compounds in Petroferric formations in the Brazilian Amazon"; Authors: Niriele Bruno Rogrigues, Theresa Rocco Barbosa, Helena Saraiva Koenow Pinheiro, Marcelo Mancini, Quentin D Read, Joshua Blackstock, Edwin Hans Winzeler, Phillip R Owens, David Miller, Zamir Libohova