"primary contributors" is a correct and usable phrase in written English.
It is used to refer to people or entities that have been primarily responsible for achieving a desired result. For example, "The primary contributors to the company's success were the dedicated employees."
This means livestock maintains its position as one of the globe's primary contributors of human-caused greenhouse gas.
Since that time, other sectors have overtaken agriculture as the primary contributors to the state's gross product.
One of the primary contributors to the atmosphere is Sabathia, one of the most unassuming superstars in sports.
But for its primary contributors, composers scattered around the globe, the site functions as a cheery virtual meeting place and a colloquium on current trends in music.
Ms. Layson noted that leak detection problems were one of the primary contributors to the spill and that the pipeline agency had levied its largest-ever civil penalty against a pipeline operator, fining Enbridge $3.7 million.
"Regardless of what sparked the fire, it is clear that the unsafe nature of this factory and the actions taken by management once the fire started were the primary contributors to the horrendous death toll".
In short, there is ample evidence that psychological factors are implicated, and from an E.M.D.R. therapy perspective, the primary contributors to these are unprocessed memories of the events that preceded the physical symptoms.
Buildings are one of the primary contributors to carbon emissions.
Primary contributors to the project to this point have been Cargill, Intel and Bitwise IO.
It remains unknown which energies are primary contributors to satellite anomalies (Choi et al. 2011).
The primary contributors to CO2 emissions are electric power generation, transport, and manufacturing.
