Links
Documentation on FPDF:
https://basepath.com/PDFbook
(online book)
https://www.elated.com/articles/create-nice-looking-pdfs-php-fpdf/
(tutorial)
http://www.fpdf.org/download/multicell.pdf
(article on MultiCell; by Tim Bonesho)
http://www.fpdf.de
(German site)
https://www.uamedwed.com/tag/fpdf
(Russian tutorials)
http://vnphp.sourceforge.net/fpdf-vi/
(Vietnamese article)
FPDF ports:
https://utelle.github.io/wxpdfdoc/
(C++)
https://github.com/eodantas/cobol-pdf
(Cobol)
https://github.com/go-pdf/fpdf
(Go)
http://lib.haxe.org/legacy/p/radpdf
(haXe)
https://github.com/nkiraly/Java-FPDF
(Java)
https://dasdeck.de/staff/valentin/lingo/pdf_class/
(Lingo)
https://code.google.com/archive/p/fpdf-plus-plus/downloads
(Lua)
https://www.dgmgdm.com/fpdf4zos/
(z/OS - MVS)
https://www.npmjs.com/package/node-fpdf
(Node.js)
https://www.npmjs.com/package/fpdf-njs
(Node.js)
https://github.com/jepafi/Free-JPDF-Pascal
(Free Pascal)
https://www.erasme.org/PL-FPDF,1337
(PL/SQL)
https://pypi.org/project/fpdf2/
(Python)
https://github.com/bollenberger/fpdf
(Ruby)
https://github.com/lamuzzachiodi/tclfpdf
(TCL)
http://www.linares.net/wxpdfcom/
(COM object, usable with VB)
https://sourceforge.net/projects/fpdfnet/
(VB.NET)
Specification documents of the PDF format:
https://opensource.adobe.com/dc-acrobat-sdk-docs/acrobatsdk/#pdf-reference