The paper can be found here: https://www.researchgate.net/publication/381041896_The_cryptoterrestrial_hypothesis_A_case_for_scientific_openness_to_a_concealed_

The paper can be found here: https://www.researchgate.net/publication/381041896_The_cryptoterrestrial_hypothesis_A_case_for_scientific_openness_to_a_concealed_earthly_explanation_for_Unidentified_Anomalous_Phenomena https://www.researchgate.net/publication/381041896_The_crypt... Without the Harvard affiliation I don't think this would make news. It's not been peer reviewed and I don't think the first author is (or claims to be) an expert on the relevant topics. (Hard to say what the relevant topics would be, maybe archeology or geology?)