The phrase "as a principal source" is correct and usable in written English.
It can be used when identifying the main or most important source of information or material in a discussion or analysis.
Example: "The study relied on data from the national census as a principal source for its demographic analysis."
Alternatives: "as a primary source" or "as a main source".
The deficit has arisen because China has displaced other countries as a principal source of supply of labor-intensive commodities.
As a principal source of horizontal stress, inversion drives significant sedimentary porosity reduction and resultant fluid flow.
- Relying on external business as a principal source of income through the openings of the state to the other side without an intermediary.
While Islam is described as the official state religion, it is regarded in the draft document as "a principal source among other sources of legislation," and not the only one.
This runoff has been recognized for at least 30 years as a principal source of water pollution on Long Island and brings with it nutrients that promote algae growth.
But as their protest began, the news Uriana had feared filtered through from Colombia: the work had already started, with a river tributary regarded by her community as a principal source of water diverted to accommodate the mine's expansion.
The authors cite the use of 'clinical judgment, that is, our collective knowledge and clinical experience' as a principal secondary source of evidence.
Recently, soybean has drawn particular attention as an energy source, since it can be used as the principal source of biodiesel, an alternative fuel.
The authors identified loose or degraded sutures in all three cases as the principal source for the development of a suture infection and subsequent endophthalmitis.
It has come to stand as the principal source of the view that geometry can be defined as a group acting on a space, and a geometrical property is any property invariant under all the transformations of the appropriate group.
First, when surveys were initially founded as the principal source of statistical information, whether one participated in a survey was largely unknown.
