Further Reading — Chapter 22: CALL and Subprogram Linkage

IBM Official Documentation

Enterprise COBOL for z/OS: Programming Guide — Chapter on "Calling and sharing data between programs." The definitive reference for CALL behavior, parameter passing, and linkage editor integration on z/OS. Available on the IBM Documentation website.
z/OS MVS Program Management: User's Guide and Reference — Covers the binder (linkage editor), load module formats, and the runtime program loading process in detail. Essential reading for understanding what happens between compilation and execution.
Language Environment Programming Reference — Documents the runtime support for inter-language communication, save area conventions, and condition handling across CALL boundaries.

Stern, Stern, and Ley, COBOL for the 21st Century, 11th Edition — Chapter 14 covers subprograms and the CALL statement with clear examples suitable for intermediate learners.
Murach, Mike, Murach's Mainframe COBOL, 2nd Edition — Chapters 17-18 provide an excellent practical treatment of subprogram design with real-world patterns. The section on copybook-based interfaces is particularly strong.
Coughlan, Michael, Beginning COBOL for Programmers — Chapter 15 offers a concise treatment of subprogram linkage with GnuCOBOL-compatible examples for students without mainframe access.

GnuCOBOL Programmer's Guide — Section on "Inter-Program Communication" covers CALL behavior in GnuCOBOL, including differences from IBM Enterprise COBOL. Available at https://gnucobol.sourceforge.io/
GnuCOBOL FAQ — Includes specific guidance on compiling and linking subprograms, static vs. shared library linking, and C interoperability.

Martin, Robert C., Clean Architecture — While not COBOL-specific, the principles of component cohesion and coupling apply directly to COBOL modular design. The Stable Dependencies Principle and the Stable Abstractions Principle inform how to structure subprogram libraries.
Parnas, David L., "On the Criteria To Be Used in Decomposing Systems into Modules" (1972) — The foundational paper on modular decomposition. Its principles — information hiding and separation of concerns — are exactly what COBOL subprogram design achieves.

Trowbridge, David, et al., Integration Patterns: Integrating Legacy Systems — Discusses strategies for wrapping COBOL subprograms as services, which builds directly on the CALL and linkage concepts from this chapter.
IBM Redbooks: "Batch Modernization on z/OS" — Covers how modular COBOL batch programs can be incrementally modernized using techniques that depend on clean subprogram interfaces.

IBM Z Xplore (https://www.ibm.com/z/resources/zxplore) — Free learning platform where you can practice compiling, link-editing, and running COBOL subprograms on a real z/OS system.
COBOL Programming Course (https://github.com/openmainframeproject/cobol-programming-course) — Open Mainframe Project's free COBOL course includes modules on subprogram development.