Dear Akshay,
Go to SE93 Transaction and collect package name(LVS) and after go to se37 tcode and click F4 function key, after click information system button enter function module name as BAPI* and package(LVS). Click enter button. These are LI20 transaction BAPI's.
BAPI_WHSE_TO_CREATE_STOCK BAPI for Stock Data per Quant
BAPI_WHSE_TO_GET_DETAIL BAPI for Header and Item Data per Transfer Order
BAPI_WHSE_TO_GET_LIST BAPI for Transfer Order List
BAPI_WHSE_STOCK_GET_DETAIL BAPI for Stock Data per Quant
BAPI_WHSE_STOCK_GET_LIST BAPI for Details of Stock per Article
Regards,
Abbas.