Horizon Information Portal

	Series	Count
1.	Discovery series	1
2.	Discovery timeline	0
3.	See Holtz, Thomas R., 1965- Discovery timeline	4
4.	Discovery travel adventures	1
5.	Discreet Retrieval Agency mysteries	0
6.	See Chance, Maia. Discreet Retrieval Agency mysteries	2
7.	Discussion paper (Hawaii. Commission on Manpower and Full Employment)	1
8.	Discworld novel	0
9.	See Pratchett, Terry. Discworld series	10
10.	Discworld series	0
11.	See Pratchett, Terry. Discworld series. Spoken word	4
12.	See Pratchett, Terry. Discworld series	10
13.	Discworld series (New York, N.Y.)	0
14.	See Pratchett, Terry. Discworld series (New York, N.Y.)	51
15.	Disease update	6
16.	Diseases and disorders	0
17.	See Diseases and disorders series	55