Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Tassili n'Ajjer' has mentioned 'Trade' in the following places:
Occurrence Sentence Text Source
[22] The arrival of camels reflects the increased development of trans-Saharan trade, as camels were primarily used as transport in trade caravans.
[29] The arrival of camels coincides with the development of long distance trade routes used by caravans to transport salt, goods, and enslaved people across the Sahara.