Omission is a perfectly legitimate expressive technique, and it's covered in many grammar books as well.
Literal
Omission [topic-は] splendid expression-technique [possessive-の] one [copula-であり], many grammar-books [in-で][also-も] introduced-[passive-されています].
省略 'omission' is discussed as a writing technique. 立派な here means 'legitimate, proper, respectable' rather than 'magnificent.' ~であり is the formal continuative copula linking two clauses, and 紹介されています is passive present — 'is introduced/covered.' The sentence defends omission as a valid technique, not an error.