The phrase "a rigorous one" is correct and usable in written English.
It can be used to describe something that is strict, thorough, or demanding, often in the context of a process, standard, or approach.
Example: "The research methodology we adopted was a rigorous one, ensuring the validity of our findings."
Alternatives: "a strict one" or "a thorough one".
The American investigation set in motion by General Sanchez appears to be a rigorous one.
Lyn Gardner contends that too many young theatre directors today studied at Oxford or Cambridge, but the award's selection process is a rigorous one that encourages applicants from diverse backgrounds.
Despite what I like to think of as a rigorous "one book in, one book out" policy, it had begun to metastasize quietly in corners, with volumes squeezed on top of the taller cabinets and in the horizontal crannies left above the spines of books that had been properly shelved.
The process of finding celebrity co-founders for 12Society was a rigorous one.
Due to the high dimensionality and non-linearity of the model, a rigorous one, the solution of the optimization problem through conventional algorithms does not always lead to convergence.
This may be a reasonable first step but is not a rigorous one, and replication across laboratories with different sets of researchers and samples is required for a true test of biomarker performance.
Dr. Lovaas, by contrast, took a behaviorist approach, proposing that autism might be ameliorated through a rigorous one-on-one program of behavior modification.
Afterwards, simulation runs based on a rigorous one-dimensional heterogeneous catalytic reactor model accounting for intra-particle gradients are performed using data obtained from model-based optimization results.
Another group, perhaps, will complete a rigorous one-year concentration in patent law, or focused course work in tax.
To earn its environmental bragging rights, the Bullitt Center must complete a rigorous one-year certification process called the Living Building Challenge, which requires both water and energy self-sufficiency, among a list of 20 demands.
The board is hoping to select the 250 fellows by the end of July and to put them through a rigorous one-month training session (board officials call it boot camp) in August.
