Reading file metadata:

$ exiftool -a matematica-elementar-livro-v2.3.8.pdf 

ExifTool Version Number         : 9.46
File Name                       : matematica-elementar-livro-v2.3.8.pdf
Directory                       : .
File Size                       : 1723 kB
File Modification Date/Time     : 2014:11:10 09:41:53-03:00
File Access Date/Time           : 2015:03:02 12:48:46-03:00
File Inode Change Date/Time     : 2014:12:15 20:33:48-03:00
File Permissions                : rw-rw-r--
File Type                       : PDF
MIME Type                       : application/pdf
PDF Version                     : 1.6
Linearized                      : No
Page Count                      : 224
Creator                         : Sejda (Ver. 1.0.0.M9)
Producer                        : iText 2.1.7 by 1T3XT
Modify Date                     : 2014:11:10 09:33:01-03:00
Create Date                     : 2014:11:10 09:33:01-03:00

/Author (Nicola Talbot)
/Title  (Creating a PDF document using PDFLaTeX)
/CreationDate (D:20040502195600)
/Subject (PDFLaTeX)
/Keywords (PDF;LaTeX)

/Title: title of the document 
/Author: author of the document 
/Creator: PDF creator 
/Producer: PDF producer 
/CreationDate: creation date 
/ModDate: modification date 
/Subject: subject of the document 
/Keywords: keywords, separated by a semicolon (;)