[1] Introduction to Uniform Type Identifiers Overview (2018-03-23 02:46:48 +09:00) https://developer.apple.com/library/content/documentation/FileManagement/Conceptual/understanding_utis/understand_utis_intro/understand_utis_intro.html

[2] Uniform Type Identifier Concepts (2018-03-23 02:47:20 +09:00) https://developer.apple.com/library/content/documentation/FileManagement/Conceptual/understanding_utis/understand_utis_conc/understand_utis_conc.html#//apple_ref/doc/uid/TP40001319-CH202-CHDHIJDE