april 1957

april 1957: 40 companies

01. april 1957 20 companies

02. april 1957 1 companies

03. april 1957 1 companies

05. april 1957 1 companies

06. april 1957 1 companies

10. april 1957 1 companies

12. april 1957 1 companies

15. april 1957 4 companies

20. april 1957 3 companies

22. april 1957 1 companies

23. april 1957 2 companies

26. april 1957 2 companies

30. april 1957 2 companies