Difference between CD4081 & 4081BD, 4081BP, 4081BT

Actually i was searching for CD4081 in NI's Multisim 11th version. Instead i found these 4081's ending with the mnemonics BD, BT AND BP. Can i use these components instead of CD4081. I want to know the main differene between all these components.
If they are different how can i get CD in the multisim?
Thanks in advance.

The D ,T, P letters will signify the different package styles available, such as DIP, or surface mount in different variations.
Hard to say without knowing which manufacturer it is.
The B specifies that it is later (in time) version, versus no letter, or an A.
Schematic capture wise it probably does not make a difference which you use, the pinouts are the per this Fairchild data sheet as an example.

If you are modeling the part for physical layout, then it will make a difference.
If you are modeling the part for elecrical performance simulation I don't think it will make a difference, the part is pretty slow and does not show different parameters for one package type vs another.

Thanks Sir.
I just want to simulate.
And what does CD mean?

CMOS Device? I don't really know, or care. It just refers to that particular family of parts.
Similar to 74, 74S, 74LS, 74AC, 74ACT, and on and on ...

A quick check at digikey.com shows:

BP = 14 pin TSSOP package
BM & BN are 14 pin SOIC packages
BC & BE are 14 pin DIP packages

To check something like this go to mouser.com or digikey.com and enter the base part number (e.g. CD4081). You'll find all the variations