The phrase "an indispensable source" is correct and usable in written English.
It can be used when referring to something that is essential or crucial for obtaining information or support.
Example: "The library is an indispensable source for researchers looking for primary documents."
Alternatives: "a vital resource" or "an essential reference".
DOWNLOAD PROSPECT HIGHLIGHTS The Internet allows amateurs to scout, and YouTube has become an indispensible source of footage.
Howard McGary and Bill E. Lawson's Between Slavery and Freedom: Philosophy and American Slavery (1992), is an indispensible source for philosophical analyses of these arguments, and the engagement of normative philosophy with historical and sociological theories of U.S. slavery.
The Encyclopedia of Food and Agricultural Ethics proves an indispensible reference point for future research and writing on topics in agriculture and food ethics for decades to come.
The Daily launched on 2 February 2011, with Murdoch saying his aim was "for the Daily to become the indispensible source for news, information and entertainment".
Sponsored research is another story, however, with federal funds accounting for 84percentt of the grant expenditures we received last year all told, $161.5 million from major players such as the National Science Foundation and National Institutes of Health and small but indispensible sources of support such as the National Endowment for the Humanities.
Nicole has supported my endeavors from the very beginning and has been an indispensible sounding board for new ideas.
Perhaps they play an indispensible role in reproduction.
RNAs form an indispensible part of the cell's architecture.
Documentation processes are an indispensible part of patient care.
Clinical education is an indispensible part of the nursing education.
For this reason, Acanthodes has become an indispensible component in early gnathostome phylogenies1,11,12,13,14,15,16,17.
