11924 Labor dispute contract of employment for definite or indefinite period of time Labor dispute period of contract of employment Proclamation 42/85 volume 3 Federal supreme court of Ethiopia cassation decisions volume 5 definite-indefinite period Labor dispute contract of employment for definite or indefinite period of time Proclamation 42/85 art. 9, 1ዐ and 24 Cassation decison no. 11924