20885 labor law dispute/ contract of employment for indefinite period of time Labor dispute period of contract of employment volume 4 Federal supreme court of Ethiopia cassation decisions definite-indefinite period ለተወሰነና ላልተወሰነ ጊዜ ስለሚደረግ የስራ ውል አዋጅ ቁ. 42/85 አንቀፅ 91ዐ Cassation 20885