Man section 5 is "File Formats and Conventions" and is not installed by default. see What do the numbers in a man page mean?
To install part of it on a Debian system, install:
sudo apt-get install libarchive-dev
From packages.debian.org:
Package: libarchive-dev (3.1.2-11+deb8u1)
The libarchive library provides a flexible interface for reading and
writing archives in various formats such as tar and cpio. libarchive
also supports reading and writing archives compressed using various
compression filters such as gzip and bzip2. The library is inherently
stream-oriented; readers serially iterate through the archive, writers
serially add things to the archive.
Double checking if man(5) tar page is installed:
dpkg -S /usr/share/man/man5/tar.5.gz
libarchive-dev:amd64: /usr/share/man/man5/tar.5.gz
Listing the files installed/owned by the package:
dpkg -L libarchive-dev | grep man
/usr/share/man
/usr/share/man/man5
/usr/share/man/man5/tar.5.gz
/usr/share/man/man5/mtree.5.gz
/usr/share/man/man5/libarchive-formats.5.gz
/usr/share/man/man5/cpio.5.gz
/usr/share/man/man3
/usr/share/man/man3/libarchive_internals.3.gz
/usr/share/man/man3/libarchive_changes.3.gz
/usr/share/man/man3/libarchive.3.gz
/usr/share/man/man3/archive_write_set_options.3.gz
/usr/share/man/man3/archive_write_open.3.gz
/usr/share/man/man3/archive_write_new.3.gz
/usr/share/man/man3/archive_write_header.3.gz
/usr/share/man/man3/archive_write_free.3.gz
/usr/share/man/man3/archive_write_format.3.gz
/usr/share/man/man3/archive_write_finish_entry.3.gz
/usr/share/man/man3/archive_write_filter.3.gz
/usr/share/man/man3/archive_write_disk.3.gz
/usr/share/man/man3/archive_write_data.3.gz
/usr/share/man/man3/archive_write_blocksize.3.gz
/usr/share/man/man3/archive_write.3.gz
/usr/share/man/man3/archive_util.3.gz
/usr/share/man/man3/archive_read_set_options.3.gz
/usr/share/man/man3/archive_read_open.3.gz
/usr/share/man/man3/archive_read_new.3.gz
/usr/share/man/man3/archive_read_header.3.gz
/usr/share/man/man3/archive_read_free.3.gz
/usr/share/man/man3/archive_read_format.3.gz
/usr/share/man/man3/archive_read_filter.3.gz
/usr/share/man/man3/archive_read_extract.3.gz
/usr/share/man/man3/archive_read_disk.3.gz
/usr/share/man/man3/archive_read_data.3.gz
/usr/share/man/man3/archive_read.3.gz
/usr/share/man/man3/archive_entry_time.3.gz
/usr/share/man/man3/archive_entry_stat.3.gz
/usr/share/man/man3/archive_entry_perms.3.gz
/usr/share/man/man3/archive_entry_paths.3.gz
/usr/share/man/man3/archive_entry_linkify.3.gz
/usr/share/man/man3/archive_entry_acl.3.gz
/usr/share/man/man3/archive_entry.3.gz
In OS/X you have already parts of the man 5 at /usr/share/man/man5 directory. Apart from copying there the aforementioned pages, have not investigated how to install them.
tar --version
and download the source for that version of libarchive. – fd0 Jul 04 '16 at 15:24