The conversation between human and AI assistant.
[|Human|] Based on the above passage name some of the companies which specialize in large-scale construction of theÂ infrastructureÂ to support oil field exploitation. Display the results in a comma separated format.
[|AI|] Hill International, Bechtel, Esso, Weatherford International, Schlumberger Limited, Baker Hughes, Halliburton
[|Human|] 
Based on the above passage name some of the companies which specialize in large-scale construction of theÂ infrastructureÂ to support oil field exploitation. Display the results in a comma separated format.