https://dds.las.ac.cn/service/document?appId=a1vacbnPuv9qJRzJvdNXfsesj9JbIa6e&appKey=sPBA4vANLzjnW1k5eufEcc4k7dxfNraW&ts=1763013203346&signature=4909b796d546f2ecfc3af5f74ef04e52&articleTitle=Symposia+on+Theoretical+Physics+and+Mathematics+9&articleAuthor=Alladi+Ramakrishnan&publicationTitle=Symposia+on+Theoretical+Physics+and+Mathematics+9&language=&publicationType=1&publishYear=1969&isn=9780306370496&publisher=Springer+US