ðə fˈɜːst klˈɪɹəns ʌv mətˈɪɹiəl əkˈɜːd dˈʊɹɹɪŋ lˈeɪt nˈaɪntiːnhˈʌndɹɪd fˈɪfti nˈaɪn ænd ˈɜːli nˈaɪntiːnhˈʌndɹɪd sˈɪksti ænd ðə sˈɛkənd ɪn dʒˈænjuːˌɛɹi nˈaɪntiːnhˈʌndɹɪd sˈɪksti fˈaɪv.
The first clearance of material occurred during late 1959 and early 1960 and the second in January 1965.