Rotblat thanks BR for his letter of 1959/03/20 (record 117286). He has been away for a few days and apologizes for not replying sooner. Rotblat explains that the Russian letter BR had enclosed (not present, record 117308) is not about Pugwash, but from the Russian journal, Philosophical Problems, asking BR to write an article on the subject of "The History of Philosophy and the Present Period".

Source: Churchill Archives Centre, RTBT 5/1/1/6 File 5.