McCoy Mark D., Alderson Helen A., Hemi Richard, Cheng Hai, Edwards R. Lawrence, November 2016, Earliest direct evidence of monument building at the archaeological site of Nan Madol (Pohnpei, Micronesia) identified using 230Th/U coral dating and geochemical sourcing of megalithic architectural stone [1] Quaternary Research, vol. 86, pp. 295–303