https://dds.las.ac.cn/service/book?appId=a1vacbnPuv9qJRzJvdNXfsesj9JbIa6e&appKey=sPBA4vANLzjnW1k5eufEcc4k7dxfNraW&ts=1730416094643&signature=37c3f29055d77b1ef2b6c81b5e73b525&name=An+essay+in+modal+logic&author=Wright%2C+Georg+Henrik+von.&publishYear=1951&isn=&publisher=Amsterdam+%3A+North-Holland+Pub.+Co.%2C+1951.%3BAmsterdam+%3A+North-Holland+pub.+co.%2C+1951.&destLibCode=311001&destLibName=中国科学院文献情报中心&agentLibCode=311001&agentLibName=中国科学院文献情报中心