The phrase "also include a substantial" is correct and usable in written English.
It can be used when you want to emphasize that something should be added or considered as part of a larger group or list, particularly when referring to a significant amount or degree.
Example: "The report should also include a substantial analysis of the market trends to support our findings."
Alternatives: "also incorporate a significant" or "add a considerable".
The sale also includes a substantial selection of photographs by Helmut Newton, as well as works by Richard Avedon, Irving Penn, Robert Mapplethorpe, and Herb Ritts.
The piece, which gives a lengthy description of the maneuvers and confrontations between the American Army and the British forces, also includes a substantial biographical sketch of Washington and his relative inexperience as a general: Washington believed that most Americans overrated his abilities as a soldier.
Blue Shift also includes a substantial section dedicated to keeping a major character in the story safe from enemy characters, and escorting him to a specific location.
But it also includes a substantial body of immigrants--namely Muslims--whom Caldwell regards as posing "the most acute problems" on account of their religion (an issue never mentioned by Powell in his speeches).
In contrast with the initial reports, we demonstrate that the Th17 phenotype is not confined to CD4+ effector cells but also includes a substantial number of naïve cells (CD45Ra) [11].
The transformation into a diazotrophic culture therefore also includes a substantial metabolic reprogramming of the vegetative cells [ 7].
Interestingly, the CGIs that were positive for all the features associated with ATRX binding also included a substantial number of imprinted DMRs.
Our present study now also includes a substantial number of Nearctic breeding marinus (n = 32) in addition to 32 samples from Palearctic breeding colonies.
This investigation also included a substantial proportion (34.8%) of professionals in their first five years of clinical work, the timeframe in which the majority[ 5] and often most serious [ 16] WRMD occur.
