https://dds.las.ac.cn/service/document?appId=a1vacbnPuv9qJRzJvdNXfsesj9JbIa6e&appKey=sPBA4vANLzjnW1k5eufEcc4k7dxfNraW&ts=1763013291571&signature=4c2ff5f9685021dbace69af24ceacf3c&articleTitle=Strings+and+Symmetries&articleAuthor=G%C3%BClen+Aktas%2C+Cihan+Saclioglu%2C+Meral+Serdaroglu&publicationTitle=Strings+and+Symmetries&language=&publicationType=1&publishYear=1995&isn=9783540591634&publisher=Springer+Berlin+Heidelberg