America First Tax-Exempt Investors, L.P.

Atlas Pipeline Partners, L.P.

Blueknight Energy Partners, L.P.

Buckeye Partners, L.P.

Centerline Holding Company

Constellation Energy Partners LLC

Crosstex Energy, L.P.

Dorchester Minerals, L.P.

El Paso Pipeline Partners, L.P.

Enbridge Energy Partners, L.P.

Enterprise Products Partners, L.P.

EV Energy Partners, L.P.

Exterran Partners, L.P.

Ferrellgas Partners, L.P.*

Genesis Energy, L.P.

Kinder Morgan Energy Partners, L.P.

Legacy Reserves, L.P.

Linn Energy, LLC

Magellan Midstream Partners, L.P.

NuStar Energy, L.P.

ONEOK Partners, L.P.

Plains All American Pipeline, L.P.

Regency Energy Partners, L.P.

StoneMor Partners, L.P.

Western Gas Partners, L.P.

Williams Partners, L.P.

W.P. Carey & Co. LLC