Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Title | Author | Reader | Format | Company | Release Date | Notes |
| --- | --- | --- | --- | --- | --- | --- |
| The Glittering Storm | Cole, Stephen Stephen Cole | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2007-11-05 5 November 2007 | An original audiobook, not published in book form. |
| The Thirteenth Stone | Richards, Justin Justin Richards | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2007-11-05 5 November 2007 | An original audiobook, not published in book form. |
| The Time Capsule | Anghelides, Peter Peter Anghelides | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2008-11-13 13 November 2008 | An original audiobook, not published in book form. |
| The Ghost House | Cole, Stephen Stephen Cole | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2008-11-13 13 November 2008 | An original audiobook, not published in book form. |
| The White Wolf | Russell, Gary Gary Russell | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2009-09-03 3 September 2009 | An original audiobook, not published in book form. |
| The Shadow People | Handcock, Scott Scott Handcock | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2009-09-03 3 September 2009 | An original audiobook, not published in book form. |
| Deadly Download | Arnopp, Jason Jason Arnopp | Sladen, Elisabeth Elisabeth Sladen | CD | BBC Audio | 2010-11-04 4 November 2010 | An original audiobook, not published in book form. |
| Children of Steel | Day, Martin Martin Day | Anthony, Daniel Daniel Anthony | CD | BBC Audio | 2011-10-06 6 October 2011 | An original audiobook, not published in book form. |
Question:
how many formats of books authored by day, martin martin day
Answer:
1.0