PMC:1315279 / 634-639 JSONTXT

{"project":"craft-sa-dev","denotations":[{"id":"T364","span":{"begin":4,"end":5},"obj":"SYM"}],"text":"am68−"}

{"project":"craft-ca-core-ex-dev","denotations":[{"id":"T153","span":{"begin":4,"end":5},"obj":"SO_EXT:sequence_nullness_or_absence"}],"text":"am68−"}