The phrase "a usual form of" is correct and usable in written English.
It can be used to describe a common or typical way of doing something or a standard method in a particular context.
Example: "In academic writing, a usual form of citation is the APA style, which provides guidelines for referencing sources."
Alternatives: "a common type of" or "a typical method of".
It's standard; an all too usual form of buyer's remorse — only Clare's experiencing it prior to sale.
The monospot, a test for the usual form of mono that can be done easily in a doctor's office, will not pick up the typhoidal version of the infection.
The usual form of a sympodium is a horizontal rootlike stem structure called a rhizome that terminates each "branch".
The admission, in a letter from Home Secretary Theresa May, followed the government's rejection of a request by Judge Robert Owen, a senior judge appointed as coroner in the Litvinenko case, to hold a public inquiry after the authorities formally prevented him from hearing sensitive evidence at an inquest, the more usual form of investigation into suspicious deaths.
The symmetry is a little obscured in the usual form of Maxwell's equations, which uses electric and magnetic fields.
In contrast to the usual form of a confidence interval ('mean value ± constant c'), here, the multiplicative forms 'mean value/factor c' and 'mean value · factor c' apply.
Further, for (beta=1), the integral boundary condition reduces to the usual form of a nonlocal integral condition (x zeta)=a int_{0}^{eta}x s),ds).
A set which satisfies |A| = |℘1(A)| is called a cantorian set, since it satisfies the usual form of Cantor's theorem.
The rocks show a shift in the relative amounts of carbon-12, the usual form of carbon, and carbon-13, a less common but stable form of carbon.
The usual form of the latter consisted of a large basin reached by a descending stairway and covered over with a vault, sometimes enclosed and sometimes supported only on piers.
