Complex sentence: Sensei's Library was started in September 2000, by the Go players Morten Pahle and Arno Hollosi, who is also known for designing version 4 of Anders Kierulf's popular SGF file format and for his work with the Austrian Citizen Card project.
Split into simpler sentences: Sensei's Library was started in September 2000, by the Go players Morten Pahle and Arno Hollosi. Hollosi is also known for designing version 4 of Anders Kierulf's popular SGF file format and for his work with the Austrian Citizen Card project.