HOUSTON Aug 7 (Reuters) - Business is so tough for oilfield giants Schlumberger NV and Halliburton Co that they have come up with a new sales pitch for crude producers halting work in the worst downturn in years.
Refer to the input text as context and select the correct relationship between 'Halliburton' and 'HOUSTON' from the available options.
Options: headquarters location, stock exchange, creator, distributed by