|
January 1981
|
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April/June 1981
|
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July/September 1981
|
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October-December 1981
|
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January/June 1982
|
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| July/September 1982 |
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| October/December 1982 |
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January/March 1983
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April/June 1983
|
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July/September 1983
|
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October/December 1983
|
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January/March 1984
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April/June 1984
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July/December 1984
|
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January 1985
|
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April 1985
|
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July/September 1985
|
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October/December 1985
|
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|
