The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE

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COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3M Co. COM 88579Y101 1,800 8,200 SH   SOLE   8,200 0 0
Advantage Oil & Gas Ltd. COM 00765F101 87,021 29,450,026 SH   SOLE   28,937,763 0 512,263
Allison Transmission Holdings Inc. COM 01973R101 207,245 5,305,823 SH   SOLE   5,157,137 0 148,686
Alphabet Inc. CAP STK CL A 02079K305 41,763 40,267 SH   SOLE   39,162 0 1,105
Altria Group Inc. COM 02209S103 1,873 30,048 SH   SOLE   30,048 0 0
American Homes 4 Rent Real Estate Investment Trust COM 02665T306 84,305 4,198,481 SH   SOLE   3,162,289 0 1,036,192
AmerisourceBergen Corp COM 03073E105 234,169 2,716,257 SH   SOLE   2,642,133 0 74,124
Apple Inc COM 037833100 190,258 1,133,971 SH   SOLE   1,109,712 0 24,259
Argo Group International Holdings Ltd. COM G0464B107 8,626 150,285 SH   SOLE   145,300 0 4,985
Armstrong Flooring Inc. COM 04238R106 11,529 849,567 SH   SOLE   604,490 0 245,077
Arthur J. Gallagher & Co. COM 363576109 102,337 1,488,971 SH   SOLE   1,092,631 0 396,340
Artisan Partners Asset Management Inc. CL A 04316A108 51,068 1,533,578 SH   SOLE   1,099,484 0 434,094
Asbury Automotive Group Inc. COM 043436104 56,586 838,315 SH   SOLE   598,338 0 239,977
AutoZone, Inc. COM 053332102 390,065 601,312 SH   SOLE   588,319 0 12,993
Axalta Coating Systems Ltd. COM G0750C108 9,754 323,075 SH   SOLE   312,343 0 10,732
Bank of Montreal COM 063671101 3,019 40,000 SH   SOLE   40,000 0 0
Bank of Nova Scotia COM 064149107 173,343 2,816,368 SH   SOLE   2,793,945 0 22,423
BB&T Corp. COM 054937107 431,224 8,286,396 SH   SOLE   8,109,857 0 176,539
Becton, Dickinson & Co. COM 075887109 169,101 780,344 SH   SOLE   759,864 0 20,480
Berkshire Hathaway Inc. CL A 084670108 108,274 362 SH   SOLE   361 0 1
Berkshire Hathaway Inc. CL B 084670702 10,767 53,976 SH   SOLE   42,257 0 11,719
Booz Allen Hamilton Holding Corp. COM 099502106 56,311 1,454,318 SH   SOLE   1,070,962 0 383,356
Brookfield Asset Management Inc. CL A 112585104 211,548 5,431,462 SH   SOLE   5,388,677 0 42,785
Brown & Brown Inc. COM 115236101 75,169 2,954,750 SH   SOLE   2,157,702 0 797,048
CBIZ Inc. COM 124805102 90,199 4,942,384 SH   SOLE   3,629,363 0 1,313,021
Canadian Natural Resources Ltd. COM 136385101 477 15,200 SH   SOLE   15,200 0 0
Canadian National Railway Co. COM 136375102 173,726 2,378,936 SH   SOLE   2,359,734 0 19,202
Celestica Inc SUB VTG SHS 15101Q108 10,437 1,009,517 SH   SOLE   913,050 0 96,467
Cenovus Energy Inc. COM 15135U109 231,671 27,230,150 SH   SOLE   26,694,209 0 535,941
Cisco Systems Inc. COM 17275R102 56,493 1,317,161 SH   SOLE   1,281,727 0 35,434
Coca-Cola Femsa S.A.B. de C.V. ADR 191241108 37,192 559,871 SH   SOLE   559,871 0 0
Colliers International Group Inc SUB VTG SHS 194693107 119,107 1,717,073 SH   SOLE   1,703,069 0 14,004
Computer Programs and Systems Inc. COM 205306103 20,234 692,942 SH   SOLE   491,862 0 201,080
Copart Inc. COM 217204106 20,488 402,275 SH   SOLE   389,264 0 13,011
Deckers Outdoor Corp. COM 243537107 47,865 531,660 SH   SOLE   388,719 0 142,941
Diageo PLC ADR 25243Q205 641 4,736 SH   SOLE   4,736 0 0
Dine Brands Global Inc. COM 254423106 45,784 698,141 SH   SOLE   516,561 0 181,580
Eaton Vance Variable Rate Income Trust COM 278279104 11,628 777,790 SH   SOLE   777,790 0 0
Enbridge Inc. COM 29250N105 231,293 7,360,009 SH   SOLE   7,301,075 0 58,934
Expedia Inc. COM 30212P303 32,934 298,289 SH   SOLE   212,904 0 85,385
Expeditors International of Washington, Inc. COM 302130109 4,007 63,304 SH   SOLE   61,235 0 2,069
Extended Stay America Inc. UNIT 30224P200 66,224 3,349,722 SH   SOLE   2,493,545 0 856,177
Federated Investors Inc. CL B 314211103 48,514 1,452,503 SH   SOLE   1,046,556 0 405,947
Franklin Resources, Inc. COM 354613101 953 27,466 SH   SOLE   27,466 0 0
Gartner Inc COM 366651107 48,380 411,321 SH   SOLE   306,107 0 105,214
Generac Holdings Inc. COM 368736104 80,034 1,743,280 SH   SOLE   1,271,910 0 471,370
Gentex Corp. COM 371901109 255,726 11,108,844 SH   SOLE   9,364,692 0 1,744,152
Graco Inc. COM 384109104 34,431 753,082 SH   SOLE   559,234 0 193,848
Harris Corp. COM 413875105 164,687 1,021,125 SH   SOLE   992,780 0 28,345
Hilltop Holdings Inc. COM 432748101 11,244 479,278 SH   SOLE   343,035 0 136,243
Houghton Mifflin Harcourt Co. COM 44157R109 45,163 6,498,219 SH   SOLE   4,840,245 0 1,657,974
Houlihan Lokey, Inc. COM 441593100 53,756 1,205,287 SH   SOLE   858,216 0 347,071
Imperial Oil Ltd. COM 453038408 11,457 432,961 SH   SOLE   431,861 0 1,100
Invitation Homes Inc COM 46187W107 29,059 1,272,855 SH   SOLE   963,916 0 308,939
Jacobs Engineering Group Inc. COM 469814107 19,355 327,224 SH   SOLE   72,773 0 254,451
Johnson & Johnson COM 478160104 406,682 3,173,482 SH   SOLE   3,106,185 0 67,297
JP Morgan Chase & Co. COM 46625H100 2,147 19,522 SH   SOLE   19,522 0 0
Kimberly Clark Corp. COM 494368103 51,852 470,822 SH   SOLE   457,722 0 13,100
The Kraft Heinz Co. COM 500754106 1,557 25,000 SH   SOLE   25,000 0 0
Laboratory Corporation of America Holdings COM 50540R409 11,392 70,429 SH   SOLE   68,135 0 2,294
Leucadia National Corp. COM 527288104 68,527 3,014,816 SH   SOLE   2,258,755 0 756,061
M & T BK Corp. COM 55261F104 213 1,154 SH   SOLE   1,154 0 0
Main Street Capital Corp. COM 56035L104 70,083 1,899,256 SH   SOLE   1,382,524 0 516,732
MarketAxess Holdings Inc. COM 57060D108 101,394 466,307 SH   SOLE   345,091 0 121,216
McDonald's Corp. COM 580135101 216,892 1,386,954 SH   SOLE   1,352,504 0 34,450
Merck & Co., Inc. COM 58933Y105 256 4,706 SH   SOLE   4,706 0 0
Microsoft Corp. COM 594918104 367,463 4,026,110 SH   SOLE   3,919,663 0 106,447
Northern Trust Corp. COM 665859104 239,532 2,322,626 SH   SOLE   2,259,738 0 62,888
Nutrien Ltd. COM 67077M108 189,276 4,008,063 SH   SOLE   3,977,876 0 30,187
Oaktree Capital Group LLC COM 674001201 15,833 399,822 SH   SOLE   215,748 0 184,074
Oppenheimer Holdings Inc. CL A 683797104 4,066 157,900 SH   SOLE   157,900 0 0
Oracle Corp. COM 68389X105 322,404 7,047,086 SH   SOLE   6,901,538 0 145,548
Pennantpark Investment Corp. COM 708062104 14,401 2,155,865 SH   SOLE   1,481,900 0 673,965
Penske Auto Group Inc. COM 70959W103 94,978 2,142,523 SH   SOLE   1,609,019 0 533,504
PepsiCo Inc. COM 713448108 248,849 2,279,879 SH   SOLE   2,231,822 0 48,057
Philip Morris International Inc. COM 718172109 267,072 2,686,841 SH   SOLE   2,620,739 0 66,102
PPG Industries Inc. COM 693506107 36,999 331,532 SH   SOLE   322,667 0 8,865
Premier Inc. CL A 74051N102 12,082 385,877 SH   SOLE   373,262 0 12,615
Primerica Inc. COM 74164M108 148,730 1,539,652 SH   SOLE   1,141,323 0 398,329
RE/MAX Holdings Inc. COM 75524W108 92,198 1,525,193 SH   SOLE   1,136,376 0 388,817
Ritchie Bros. Auctioneers Inc. COM 767744105 133,994 4,257,847 SH   SOLE   4,223,540 0 34,307
Royal Bank of Canada COM 780087102 174,844 2,265,298 SH   SOLE   2,245,901 0 19,397
Sabre Corp. COM 78573M104 388,615 18,117,265 SH   SOLE   17,713,687 0 403,578
Sally Beauty Holdings Inc. COM 79546E104 72,726 4,421,030 SH   SOLE   3,308,562 0 1,112,468
Shaw Communication Inc. CL B CONV 82028K200 98,720 5,128,455 SH   SOLE   5,088,651 0 39,804
SS&C Technologies Holdings Inc. COM 78467J100 154,175 2,874,247 SH   SOLE   2,145,958 0 728,289
Strayer Education Inc. COM 863236105 53,453 528,973 SH   SOLE   390,654 0 138,319
TCP Capital Corp. COM 87238Q103 45,683 3,212,557 SH   SOLE   2,294,695 0 917,862
TE Connectivity Ltd. REG SHS H84989104 1,542 15,439 SH   SOLE   14,994 0 445
Tempur Sealy Intly Inc. COM 88023U101 21,312 470,572 SH   SOLE   334,099 0 136,473
Texas Instruments Incorporated COM 882508104 133,826 1,288,154 SH   SOLE   1,253,329 0 34,825
Toronto-Dominion Bank COM 891160509 175,081 3,087,776 SH   SOLE   3,060,840 0 26,936
Transcanada Corp. COM 89353D107 128,264 3,104,032 SH   SOLE   3,079,048 0 24,984
Union Pacific Corp. COM 907818108 490,163 3,646,233 SH   SOLE   3,561,859 0 84,374
United Technologies Corp. COM 913017109 429,596 3,414,369 SH   SOLE   3,337,016 0 77,353
Waddell & Reed Financial, Inc. CL A 930059100 21,395 1,058,628 SH   SOLE   752,925 0 305,703
Walgreens Boots Alliance, Inc. COM 931427108 404,286 6,175,133 SH   SOLE   6,042,974 0 132,159
White Mountains Insurance Group Ltd. COM G9618E107 32,615 39,652 SH   SOLE   30,287 0 9,365